Inhibition of peptide cleavage in plants

ABSTRACT

The invention provides a system for expressing a foreign peptide in a plant cell, wherein the foreign protein is sensitive to a protease activity in the plant cell, by introducing into a plant cell a polynucleotide, which encodes the foreign protein and an another polynucleotide, which encodes a genetic element capable of reducing the protease activity in the plant cell. The invention also provides for plant cells, which incorporate this system, and for methods of reducing the proteolysis of the foreign protein expressed in a plant cell by using this system.

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims benefit of the filing date of U.S. Provisional Application No. 60/396,396 filed Jul. 16, 2002 and is incorporated herein by reference.

FIELD OF THE INVENTION

[0002] This present invention is related to the field of plant molecular biology and expression of a protein in a plant host. In particular, this invention relates to the inhibition of peptide cleavage of the protein by a protease native to the plant host. The inhibition is effected by the use of a recombinant nucleic acid, which is inserted into a heterologous virus or by plant transformation to inhibit the protease activity in the plant host.

BACKGROUND OF THE INVENTION

[0003] Proteolytic enzymes or proteases are enzymes that function by catalyzing the cleavage of peptide bonds in proteins. Proteases are ubiquitous in nature and are involved with both random and site-specific cleavage of peptide bonds. Table 1 lists the major families of proteolytic enzymes and their corresponding active site residues (Neurath, 1984). Proteolytic function is determined in part by the structural arrangement of these amino acid residues. TABLE 1 Families of proteolytic enzymes Family¹ Representative protease(s) Active site residues² A. Serine Protease I Chymotrypsin (EC 3.4.21.1) Asp¹⁰², Ser¹⁹⁵, Trypsin (EC 3.4.21.1) His⁵⁷ Elastase (EC 3.4.21.11) Pancreatic Kallikrein (EC 3.4.21.8) B. Serine Protease II Subtilisin (EG 3.4.21.14) Asp³², Ser²²¹, His⁶⁴ C. Cysteine Papain (EC 3.4.22.2) Cys²⁵, His¹⁵⁹, proteases Actinidin Asp¹⁵⁸ Rat liver cathepsins B & H D. Aspartic Protease Penicillopensin (EC 3.4.23.6) Asp³³, Asp²¹³ Rhizopus Chineses, acid protease Endothia Parasitica, acid proteases Rennin (EC 3.4.99.19) Pepsin (EC 3.4.23.1) Chymosin (EC 3.4.23.4) E. Metallo-Protease Bovine carboxypeptidase A Zn, Glu²⁷⁰, Try²⁴⁸ I (EC 3.4.17.1) F. Metallo-Protease Thermolysin (EC 3.4.24.4) Zn, Glu¹⁴³, His²³¹ II

[0004] Chymotrypsin- and subtilisin-like serine proteases are the largest groups of the serine protease family. The arrangement of the amino acid residues aspartate, histidine and serine in the catalytic triad is highly conserved in both, with differences occurring primarily in the protein scaffolding (Siezen and Leunissen, 1997). Proteases, in general, exist as pre-proteins that are functionally inactive until cleavage of the targeting peptide (Neurath, 1984). Subtilisin-like serine proteases exist as pre-proenzymes (Gensberg, Jan, and Matthews, 1998; Neurath, 1984; Siezen and Leunissen, 1997). The pre-peptide (or signal peptide) acts as a targeting sequence to direct the proenzyme outside the cell via the secretory pathway and cleavage of the pro-peptide results in the active protease. The prodomain of subtilisin-like proteases has been implicated in serving specific regulatory functions associated with the protease. These include, chaparonin-like folding properties (Creemers, Jackson, and Hutton, 1998; Gensberg, Jan, and Matthews, 1998; Yamagata et al., 1994), correct temporal and spatial activation (Creemers, Jackson, and Hutton, 1998; Tomero, Conejero, and Vera, 1996; Yamagata et al., 1994), and intracellular transport, stability and sorting (Creemers, Jackson, and Hutton, 1998; Gensberg, Jan, and Matthews, 1998).

[0005] Mammalian subtilisin-like serine proteases are known to be involved in the processing of numerous biologically important prohormones and proproteins (Barr, 1991; Creemers, Jackson, and Hutton, 1998; Gensberg, Jan, and Matthews, 1998; Steiner et al., 1992). These proteases act within the secretory pathway to cleave specific basic amino acid residues thus generating the active molecule (Gensberg, Jan, and Matthews, 1998). The most common processing sites found in mammalian subtilisin-like proteases are pairs of basic amino acid residues Lys:Arg and Arg:Arg, but cleavage motifs including mono-, tri-, tetra- and pentabasic residues have also been characterized (Barr, 1991). Some examples of proteins catalyzed by mammalian subtilisin-like proteases include; nerve growth factor, proinsulin C, insulin proreceptor, proalbumin, and prorenin.

[0006] Human growth hormone (hGH), a major protein of the pituitary gland and involved in numerous regulatory functions (Sinha and Jacobsen, 1994), exists as a prohormone and is processed in vivo, giving rise to catalytically active peptide fragments (Creemers, Jackson, and Hutton, 1998; Salem, 1988; Sinha and Jacobsen, 1994). Proteolytic processing can occur in an exposed domain of the large disulfide region of the hGH protein (Gellerfors et al., 1990; Wroblewski, Kaiser, and Becker, 1993). An in vitro study using biosynthetic hGH and thyroid gland extracts rich in a protease that was similar to a chymotrypsin-like serine protease showed metabolic intermediates were formed exclusively by cleavage carboxy to the tyrosine, phenylalanine or leucine amino acid residues (Wroblewski, Kaiser, and Becker, 1993).

[0007] Stem cell factor from various species and variants are known to have a variety of desirable biological activities. See Zhang et al, Biology of Reproduction 50:95-102, Davis et al, Cytokine 9(4): 263-275 (1997), WO 96/18726 and WO 97/38101.

[0008] Plant subtilisin-like serine protease genes (Ribeiro et al., 1995; Tornero, Conejero, and Vera, 1996; Yamagata et al., 1994), have been isolated and have been subgrouped into the Pyrolysin family of subtilisin-like proteases (Siezen and Leunissen, 1997). As is typical of subtilisin-like proteases (Barr, 1991; Gensberg, Jan, and Matthews, 1998), plant subtilisin-like genes also encode proteins that are synthesized as pre-proenzymes. These proteases have been implicated in many different aspects of plant development. Tissue specific gene expression has been reported in pollen (Taylor et al., 1997), fruit (Rudenskaya et al., 1995) etc. Specific plant proteases and protease inhibitors are induced as part of a cascade of defense-related activities (Tornero, Conejero, and Vera, 1996; Tomero, Conejero, and Vera, 1997). Additionally, studies using reporter gene constructs to the promoters of two pathogen-induced tomato subtilisin-like protease genes revealed induced reporter gene activity following challenge with either Pseudomonas syringae or salicylic acid (Taylor et al., 1997).

[0009] Plant subtilisin-like proteases have broad substrate specificity (Siezen and Leunissen, 1997). Unlike mammalian proteases, the plant subtilisin-like proteases studied to date prefer cleaving amino acids with bulky hydrophobic or aromatic side chains (Yamagata et al., 1994). In vitro studies have determined that processing frequently occurs at sites similar to those targeted by chymotrypsin-like serine proteases (Kaneda, Yonezawa, and Uchikoba, 1995; Wroblewski, Kaiser, and Becker, 1993; Yamagata et al., 1994).

[0010] Because plant subtilases have been detected in numerous plant tissues (Ribeiro et al., 1995; Rudenskaya et al., 1998; Rudenskaya et al., 1995; Tomero, Conejero, and Vera, 1996; Tomero, Conejero, and Vera, 1997; Yamagata et al., 1994) the recombinant expression of heterologous sequences in plants may be problematic for some proteins. Some plant proteases may have a high affinity for certain heterologous proteins that are being expressed. In particular, proteins such as human growth hormone, that are proteolytically processed in nature by enzymes with substrate specificities similar to those that have been identified in plants, may be susceptible to degradation in planta or in contact with plant extracts.

SUMMARY OF THE INVENTION

[0011] The present invention provides for a plant cell comprising one or more polynucleotides, wherein the one or more polynucleotides encode a protein of interest and one or more genetic element(s) capable of reducing a protease activity in a plant cell, wherein the polynucleotides are capable of expressing the protein of interest in the plant cell, wherein the protease activity is capable of cleaving the protein of interest, wherein the protein of interest is preferably non-native to the plant cell.

[0012] The present invention also provides for a plant cell comprising a non-native polynucleotide, wherein the polynucleotide encodes a protein of interest, wherein the polynucleotide is capable of expressing the protein of interest in the plant cell, wherein the polynucleotide comprises a genetic element capable of reducing a protease activity in the plant cell, wherein the protease activity is capable of cleaving the protein of interest, wherein the protein of interest is preferably non-native to the plant cell.

[0013] The present invention further provides for a method of reducing the amount of a protein of interest cleaved by a protease activity in a plant cell, comprising the steps of:

[0014] (a) introducing a polynucleotide into a plant cell, wherein the first polynucleotide comprises a genetic element capable of reducing a protease activity in the plant cell; and

[0015] (b) expressing a protein of interest in the plant cell, wherein the protein of interest is heterologous to the plant cell, wherein the protein of interest is capable of expression in the plant cell, whereby the amount of protein of interest cleaved by the protease activity in the plant cell is reduced compared to the amount of protein of interest cleaved by the protease activity in another plant cell in which the first polynucleotide is not introduced.

[0016] The present invention also provides for a protein of interest, or one or more fragments thereof, produced using the subject plant or plant cell and/or subject method. The present invention further provides for a polynucleotide comprising the genetic element capable of reducing a protease activity in a plant or a plant cell. The present invention further provides for a polynucleotide comprising the (1) coding sequence of a Nicotianalisin protein, or one or more fragments thereof, or (2) a sequence with substantial similarity to one or more conserved region of the Nicotianalisin protein, which is capable of specifically hybridizing to a second polynucleotide encoding a related protease protein for the purpose of identifying the second polynucleotide from a mixture of known or unknown polynucleotides.

[0017] Novel plant protease Nicotianalisin and similar protease genes may be cloned per se and then used to produce the active enzyme as a product per se.

BRIEF DESCRIPTION OF THE FIGURES

[0018]FIG. 1 depicts the in vitro stability of expressed recombinant human growth hormone protein (hereafter “hGH”) in the interstitial fluid (hereafter “IF”) following the addition of protease inhibitors. Recombinant hGH protein was expressed in N. benthamiana using a tobacco mosaic virus (hereafter “TMV”) vector expression system. IF was prepared from plant leaves at 9 days post-inoculation and incubated for 24 hours at 24° C. followed by 120 hours at 5° C. with or without the addition of protease inhibitors. Fifteen microliters of the IF extract was separated by SDS-PAGE and the gel prepared for Western analysis. The levels of hGH protein in the IF of the time zero control (lane a), in absence of inhibitor (lane b), and in the presence of protease inhibitors chymostatin (lane c) and PI-I (lane d), were detected using anti-hGH antibody.

[0019]FIG. 2 depicts the inhibition of Nicotianalisin by PMSF protease inhibitor using Zymogram gelatin gel analysis. Plant extracts containing Nicotianalisin activity were partially purified by ion-exchange chromatography at pH 5.2, and fractions with peak protease activity were treated with or without 2 mM PMSF for 1 hr at 24° C. Following treatment, aliquots were removed and inhibitory activity assessed on Zymogram gels.

[0020]FIG. 3 depicts the SDS-PAGE gel of fractions from N. benthamiana subtilisin-like protease purification. A subtilisin-like protease was purified from virally-infected N. benthamiana leaf IF using column chromatography and 2.5 μg total protein was loaded per lane. Lanes are as follows: (MW) molecular weight markers; (1) plant IF extract; (2) butyl Sepharose; (3) DEAE Sepharose; (4) Sephacryl 100; and, (5) Superose-12. The gel was stained with Coomassie blue.

[0021]FIG. 4 depicts the N-terminal sequence comparison of Nicotianalisin and other plant subtilisin-like proteases. The N-terminus of the mature protein of Nicotianalisin purified from N. benthamiana leaves was aligned with eleven other plant subtilisins using DNAMAN Multiple Alignment software (Lynnon BioSoft). A consensus sequence of greater than 75% identity was generated.

[0022]FIG. 5 depicts the Nicotianalisin enzyme activity pH optimum. Aliquots of purified Nicotianalisin protease were assayed for proteolytic activity, and the pH optimum was determined. Enzyme assays were conducted at 37° C. in 0.1 M Tris-propane containing 5 mM CaCl₂, pH range from 6 to 10.5. N-Suc-AAPF-pNA SEQ ID NO: (Del Mar et al., 1980; Del Mar et al., 1979) was used as a substrate at 0.3 mM concentration in the reaction mixture. The absorbance of the p-nitroaniline produced was measured at 410 nm. Values are shown as percentages of the maximum activity.

[0023]FIG. 6 depicts the proteolytic activity of Nicotianalisin and other plant subtilisin-like proteases (Rudenskaya et al., 1998) on oxidized bovine insulin B chain. An aliquot of the Nicotianalisin protease was mixed with pure insulin B chain protein, incubated for 1 hr at 37° C., and the mass of the cleavage products assayed by MALDI-TOF Mass Spectrometry. The cleavage specificities of Nicotianalisin and other plant subtilisins are indicated.

[0024]FIG. 7 depicts the activity of a purified protease, Nicotianalisin, against hGH protein in in vitro assays. An aliquot of Nicotianalisin protease was mixed with purified hGH protein at a 1:50 ratio of protease:substrate, incubated for 10-30 min at 30° C. and peptide fragments analyzed by Coomassie-stained SDS-PAGE. Lanes are as follows (from left to right): (1) molecular weight markers (Invitrogen, Multimark); (2) protease/substrate incubated for 10 min; (3) protease/substrate incubated for 20 min; (4) protease/substrate incubated for 30 min; (5) substrate only incubated for 10 min; (6) substrate only incubated for 20 min; and, (7) substrate only incubated for 30 min.

[0025]FIG. 8 depicts the Western blot of hGH cleaved by purified Nicotianalisin protease. An aliquot of Nicotianalisin protease was mixed with purified hGH protein at a 1:50 ratio of protease:substrate and incubated for 10-30 min at 30° C. Lanes are as follows (from left to right): (1) molecular weight markers (Novex Prestained markers); (2) protease/substrate incubated for 10 min; (3) protease/substrate incubated for 20 min; (4) protease/substrate incubated for 30 min; and, (5) substrate only incubated for 30 min, as a control.

[0026]FIG. 9 depicts a DNA agarose gel of the products of RT-PCR-amplification of subtilisin-like protease cDNA. Total RNA was isolated from N. benthamiana (Nb) and Arabidopsis thaliana (At) and used as template to RT-PCR amplify a protease cDNA.

[0027]FIG. 10 depicts the deduced amino acid sequence alignment of N. benthamiana (Nb) gene fragment contigs, NbP3 and NbP6, SEQ ID NO: 24 and 25, respectively, and the tomato p69A sequence (Tomero, Conejero, and Vera, 1996). The alignment was performed using DNAMAN Multiple Alignment software. Active site residues are in bold and indicated with asterisk. N-linked glycosylation sites are italicized and underlined. The consensus line indicates amino acid residues that are 100% identical in all three sequences.

[0028]FIG. 11 depicts the amino acid sequence alignment of Nicotianalisins (SEQ ID NO: 18 to 29, 39 to 40; including both partial and full open reading frames (ORF) based on deduced amino acid sequence of N. benthamiana cDNA clones) and fourteen other subtilisin-like proteases. These proteases are AG12 (Genbank accession #S52769), AIR3 (Genbank accession #AAD12260), ARA12 (Genbank accession #AAC18851), CUSSP (Genbank accession #BAA06905), F22M8.3 (Genbank accession #AAF76468), MDC16.21 (Genbank accession #BAB02339), P69A (Genbank accession #CAA76724), P69B (Genbank accession #CAA76725), P69C (Genbank accession #CAA76726), P69D (Genbank accession #CAA76727), SBT1 (Genbank accession #CAA06999), SBT2 (Genbank accession #CAA07000), SBT3 (Genbank accession #CAA07001), SBT4 (Genbank accession #CAA06998). The alignment was performed using DNAMAN Multiple Alignment software. A consensus sequence was generated from residues identical in greater than 50% of the sequences. The underlined bold residue (at position 125 of the consensus) indicates the putative start of the mature protein. Bold and italicized residues (at positions 161, 237, and 581 of the consensus) indicate the residues involved in the catalytic triad. Sequences of peptides that were isolated and identified from the N. benthamiana IF are shaded on SEQ ID NO: 18 and 19. The alignment was performed using the DNAMAN Multiple Alignment software.

[0029]FIG. 12(A) and (B) depict a tobacco mosaic virus (TMV)-based viral vector construct map containing SEQ ID NO: 3 in an antisense (A) or sense (B) orientation. MP—movement protein; CP-coat protein.

[0030]FIG. 13 depicts the plant viral vector mediated down regulation of protease activity in inoculated N. benthamiana leaves. The SEQ ID NO: 3 cDNA gene fragment was cloned into a TMV-based plant viral vector in the antisense orientation. The DNA was transcribed, and infectious RNA was used to inoculate N. benthamiana plants. At 10 days post-inoculation the plant IF fraction was harvested and assayed for inhibition of proteolytic activity using substrate-embedded Zymogram gels. Five μl of uninoculated (lane 1), viral vector control-treated (green fluorescent protein (GFP), (lane 2), or viral vector antisense-treated (lane 3) plant IF extracts were separated on a Zymogram gel and analyzed for gel clearing.

[0031]FIG. 14 depicts tobacco rattle virus (TRV) RNA2 construct maps containing SEQ ID NO: 3 in the sense or antisense orientation. CP ORF—coat protein; 2b ORF— non-structural protein; PEBV CP SGP—pea early browning virus coat protein subgenomic promoter.

[0032]FIG. 15 depicts the accumulation of recombinant hGH protein using a TRV Nicotianalisin silencing vector and a TMV protein expression vector. Two weeks post-sowing N. benthamiana plants were infected with TRV RNA-1 plus RNA-2 containing a 1.2 kb fragment of SEQ ID NO: 3 in the sense orientation. At 9 days post-inoculation, the N. benthamiana plants were infected with a TMV-based expression vector containing the hGH gene. TMV-infected plants were harvested after an additional 10 days. Plant IF extracts were separated by SDS-PAGE and the gel prepared for Western analysis. The immunoblot was probed with polyclonal anti-hGH antibody. 16 μl of IF extract from plants inoculated with TMV-hGH alone (lane 2), TRV silencing construct and TMV-hGH (lane 3), TRV silencing construct alone (lane 4) or buffer alone (lane 5) were loaded per lane and 20 ng of pituitary gland hGH protein (lane 1) were used as a standard.

[0033]FIGS. 16A and 16B depict the nucleotide sequence alignment and its phylogenetic tree, respectively, of 15 N. benthamiana subtilisin-like proteases. The bold and italic nucleotides on the consensus sequence indicate the approximate area of the conserved regions A and B. Bold and italic nucleotides on individual SEQ ID indicate the variable region specific to that SEQ ID. Sequences from these regions were chosen as a target for silencing one or more of the Nicotianalisins. FIG. 16B is a phylogenic tree of the sequences. On FIG. 16B, the number next to a line represents the branch length. The alignment was performed using DNAMAN Multiple Alignment software.

[0034]FIG. 17 depicts a GENEWARE® plant viral vector containing the replicase, the movement protein and the heterologous gene aprotinin fused to human and porcine Stem Cell Factor containing a His tag. The subsequent cleavage in vivo or in vitro to release the Stem Cell Factor is depicted by way of Kex-2p protease or the like. (Schaller et al, Proc. Nat. Acad. Sci. 91: 11802-11806 (1994))

[0035]FIG. 18 depicts a Coomassie blue stained SDS gel of plant extracts proteins where the plants were infected by various GENEWARE® vectors. Each vector contained different foreign genes to be expressed in the plant. Total grind extracts of plants infected with viral vectors expressing hSCF or pSCF with C-terminal HDEL ER-targeting signals are shown. IF extracts from plants infected with viral vectors containing Aprotinin alone, hSCF, pSCF, hSCF with an N-terminal fusion to Aprotinin, and pSCF with an N-terminal fusion to Aprotinin are shown. A control lane containing purified natural aprotinin and a lane of molecular weight standards (unmarked) are included for comparison purposes.

[0036]FIG. 19 depicts a Western blot of an SDS-PAGE gel separating various plant extracts proteins where test lanes were from plants infected with a plant viral vector containing and expressing either hSCF or pSCF or derivatives thereof as a heterologous gene. E. coli produced recombinant hSCF, uninfected plants (healthy), a GENEWARE® vector with a gfp gene as the heterologous insert (clone 5) and labeled molecular weight standards are provided as controls for comparison. Antibody against hSCF was used to detect SCF proteins and fragments in the gels.

[0037]FIG. 20 depicts a Western blot of various plant extract proteins comparing stem cell factors yield with and without expressing an aprotinin gene. Antibody against human SCF was used to label SCF proteins and their fragments in the gels. The molecular weight of the SCFs and the degradation products are shown.

DESCRIPTION OF THE SPECIFIC EMBODIMENTS

[0038] Definitions and Abbreviations

[0039] Virus-based vector or viral vector means an engineered host virus that is capable of expressing a desired protein or trait in a host.

[0040] Expression means transcription, translation, protein synthesis, posttranslational modification or any combination of transcription, translation, protein synthesis and posttranslational modification.

[0041] Foreign gene means any nucleic acid that is not derived from or extracted from or native to a host into which it is inserted.

[0042] Reporter protein means a protein which, when expressed by a viral vector, allows detection of virus-infected cells.

[0043] Host means a cell, tissue, organ, or organism capable expressing the ORFs of the subject polynucleotides. This term is intended to include prokaryotic and eukaryotic cells, organs, tissues or organisms, where appropriate. Bacteria, fungi, yeast, animal (cell, tissue, organ, or organism, including human), and plant (cell, tissue, organ, or organism) are examples of a host.

[0044] Infection means the ability of a virus to transfer its nucleic acid to a host or introduce a viral nucleic acid into a host, wherein the viral nucleic acid is replicated and viral proteins are synthesized.

[0045] ORF or open reading frame means a nucleotide sequence encoding a series of sense codons that lacks a termination codon within it. The ORF may be encoded in any nucleic acid, including DNA or RNA, and the nucleic acid may be any form, including single-stranded or double-stranded. An ORF may encode a peptide that is expressed and may be a gene.

[0046] Substantial sequence similarity is present between two nucleic acid or amino acid sequences when the nucleotide or amino acid sequence of a stretch of at least 10 consecutive nucleotides or amino acids of the two are 50% or more identical to each other.

[0047] The Invention

[0048] The invention provides for a polynucleotide encoding a genetic element capable of directly or indirectly reducing a protease activity in a plant cell.

[0049] The invention also provides for a plant cell comprising a first polynucleotide and a second polynucleotide, wherein the first polynucleotide encodes a protein of interest, wherein the first polynucleotide is capable of allowing expression of the protein of interest in the plant cell, wherein the second polynucleotide comprises a genetic element capable of reducing a protease activity in the plant cell, wherein the protease activity is capable of cleaving the protein of interest, wherein the protein of interest is preferably non-native to the plant cell.

[0050] The invention also provides for a plant cell comprising a non-native polynucleotide, wherein the polynucleotide encodes a protein of interest, wherein the polynucleotide is capable of allowing expression of the protein of interest in the plant cell, wherein the polynucleotide comprises a genetic element capable of reducing a protease activity in the plant cell, wherein the protease activity is capable of cleaving the protein of interest. The protein of interest is preferably not native to the plant cell.

[0051] The genetic element capable of reducing a protease activity in a plant cell or fluids: (1) is or expresses an RNA transcript capable of reducing expression of a protein with the protease activity in the plant cell, (2) induces expression of a protease inhibitor native to the plant cell in the plant cell, (3) is or expresses a protease inhibitor in the plant cell, (4) is or expresses a repressor of the protease gene, (5) is or expresses a nucleic acid or expresses a protein which up or down regulates a different protein which results in the down regulation of the protease gene, (6) induces a site specific mutation in the protease gene, (7) is or induces expression of a triple strand binding nucleic acid which binds at or near the protease gene, 8) is or induces expression of an artificial binder to the protease gene, 9) is or induces expression of a binder for the protein of interest which protects the protein of interest from the action of the protease, 10) is or expresses an agent to reduce mobility of the protease or to retard protease secretion into the IF or 11) induces expression of a protein or nucleic acid which degrades or increases the degradation of the protease. The direct or indirect protease activity inhibitory activity may require additional cellular or fluid components for functioning. Likewise, the protease activity inhibitory activity may act on other cellular or fluid components, which enhance protease activity of the protease enzyme, such as a cofactor.

[0052] An RNA transcript capable of reducing expression of a protein may be an antisense transcript, a sense transcript, or a ribozyme. The antisense transcript is antisense to one or more proteases and is able to reduce, silence, or completely shut off expression of the one or more proteases. The sense transcript is sense to one or more proteases and is able to reduce, silence, or completely shut off expression of the one or more proteases. The antisense or sense element comprises a nucleotide sequence that is substantially homologous to the antisense or sense nucleotide sequence of a protease. Preferably, the antisense or sense element comprises the antisense or sense nucleotide sequence of the protease. The ribozyme is able to recognize mRNA encoding the one or more proteases in order to catalyze cleavage of the mRNA, which brings about the reduction, silence, or complete shut off of expression of the one or more proteases. The genetic element can be designed to specifically reduce the protease activity of one or more specific proteases in a plant cell by encoding a polypeptide protease inhibitor. The quantity of protease may also be reduced by a natural or artificial repressor or inducer analog (which does not induce) encoded by the genetic element. The protease gene itself may be mutated or inactivated by a genetic element that elicits a site-specific mutation in or near the protease gene or its regulatory elements. Such site specific mutations may be induced to create a missense codon, a non-sense codon, a frameshift mutation, an insertion in or a deletion of a portion of the protease gene. Such mutagenesis may be formed by the genetic element or its expression product. Reactive chemicals may enhance the mutation of the protease gene.

[0053] Antisense or sense RNA may also be polymerized and/or be fused with bulk polynucleotides to adsorb RNA or to bind to DNA where the bulk polynucleotides or polymers of antisense RNA act as insolubilizing, blocking or sequestering agents for binding to the RNA or DNA, thereby inhibiting synthesis of a protease. The RNA may have an additional polynucleotide sequence which binds to natural cellular compounds and structures to further localize it and the corresponding polynucleotides for the protease activity.

[0054] The protease can be native or non-native to the plant cell. The protease can be any protein with direct or indirect protease activity. Preferably, the specific proteases belong to one or more class of proteases. More preferably, the specific proteases of each class of protease have nucleic acid and/or amino acid sequence similarity or contain conserved or identical amino acid residues. Preferably, the protease can be any protein with a chymotrypsin-like serine protease or a subtilisin-like serine protease activity. More preferably, the protease can be any protein with a Nicotianalisin protease activity.

[0055] Preferably, the protease is a serine protease, or a functional fragment thereof. “Functional fragment” means a peptide comprising the minimum amino acids of the catalytic site of the protease wherein the peptide retains the proteolytic activity of the protease (i.e., all or part of the activity of the wild-type protein). More preferably, the protease is a chymotrypsin-like serine protease or a subtilisin-like serine protease. Even more preferably, the protease is a Nicotianalisin protein.

[0056] The protein of interest can be a peptide of virtually any amino acid sequence as long as the protein of interest is capable of being expressed in the host cell. The protein of interest can be a protein sensitive to the protease activity to be reduced. The protein of interest can be a plant or a non-plant protein. Microbial proteins may be proteins of interest, particularly those used for vaccine purposes. The non-plant protein can be an animal protein. The animal protein can be a human protein. Representative examples of such proteins of commercial interest produced in recombinant plants include: human growth hormone, chicken interferon, human single chain antibody, human insulin, human alpha-galactosidase, etc.

[0057] The protein of interest may even be a protein beneficial to the plant itself and not particularly for isolation therefrom. Insecticidal proteins such as endotoxins from Bacillus thuringensis or non-BT proteins such as VIP3A, cholesterol oxidases, alpha amylase inhibitors, septic wound response proteins, serine protease inhibitors, trypsin inhibitors, chitinase, Beta-1,3-glucanase, etc, may be produced as pesticides. Note Estruch et al, Nature Biotechnology 15:137-141 (1997) and Ryan, Ann. Rev. Cell. Biol. 3:295-317 (1987). Anti-fungal proteins, e.g. Ye et al, Life Sci. 7;67(7):775-81 (2000), Mitsuhara et al, Mol Plant Microbe Interact. August;13(8):860-8 (2000) may also be likewise used. Protein toxins against mammals and birds may also be used provided that the plant is a non-food crop.

[0058] Other desirable traits, such as flower or leaf color, salt tolerance, herbicide resistance, proteins altering secondary metabolite concentration, etc., may also be affected using the techniques of the present invention.

[0059] Anti-proteosome function activity is included as a form of inhibiting protease activity. Proteosome destabilization and associated protein degradation are considered a type of protease activity. Inhibitors include organic metabolites such as MG 132 and Lactacystin as well as oligo-leucine based peptides such as Calpin inhibitor III.

[0060] Another aspect of this present invention is a polynucleotide comprising the sequence (or complementary sequence) of a conserved region, or fragment thereof, of the protease mentioned earlier. The sequence (or complementary sequence) of a conserved region is either identical or substantially similar to the conserved regions. FIG. 16 discloses the nucleic acid sequences of such conserved regions. “Substantially similar” means a stretch of nucleotides with sufficient identity so that the sequence is capable of hybridizing to a nucleic acid comprising the conserved sequence. “Substantially similar” can be 50% or more of nucleotide identity. Preferably, it is 70% or more of nucleotide identity. More preferably, it is 80% or more of nucleotide identity. Even more preferably, it is 90% or more of nucleotide identity.

[0061] It is recognized that different strains and different species of plants may have slightly different analogous proteases. Furthermore, certain nucleotide changes or even amino acid changes may be employed to alter expression and even to change the protease activity or specificity.

[0062] The chemical structures of the inhibitors of protease activity may be diverse. A polypeptide expressed by the genetic element may be such an inhibitor by a number of mechanisms. Alternatively, an RNA expressed by the genetic element may be such an inhibitor by either hybridization, silincing enzymatic functioning or acting as a binding aptamer. A DNA genetic element itself may have the same functions as the RNA to inhibit the protease activity. Any of the polynucleotides mentioned above can be a nucleic acid, a recombinant nucleic acid, a recombinant viral nucleic acid, a genomic nucleic acid component, a subgenomic nucleic acid, a recombinant polynucleotide, or the like. The polynucleotide may be DNA or RNA, either double-stranded (“ds”) or single-stranded (“ss”). ss DNA or ss RNA can be either positive- or plus-sense, or negative- or minus-sense.

[0063] The polynucleotide may also comprise synthetic nucleic acid or nucleotides in the stead of DNA or RNA, such as a derivative resistant to degradation in vivo, as discussed below. Within this specification, references to DNA or RNA apply, mutatis mutandis, to other nucleic acids as well, unless clearly forbidden by the context. The bases may be the “normal” bases adenine (A), guanine (G), thymidine (T), cytosine (C) and uracil (U), or abnormal bases such as a synthetic base.

[0064] The polynucleotide may be prepared by any desired procedure. The polynucleotide can be synthesized using an automated DNA synthesizer, such as the ABI™ 3900 High-Throughput DNA Synthesizer (Applied Biosystems, Foster City, Calif.).

[0065] The polynucleotide may comprise a vector, construct, plasmid, episome, virus, transposon, naked or packaged (e.g. in a liposome) nucleic acid, replicon, or the like. The polynucleotide can be capable of stable replication in one or more of a tissue, a host, a bacterial cell, a prokaryotic cell, an eukaryotic cell, a yeast cell, an animal cell, especially an insect cell, a plant cell, a plant protoplast cell, or the like, for the purpose of amplification. The polynucleotide may be viral and may be recombinant or both. The polynucleotide may comprise a viral or other expression vector or a recombinant expression vector. The polynucleotide can remain extra-chromosomal and need not integrate into any host or organelle chromosome. The polynucleotide can be maintained in the cytoplasm or other compartment of the host and does not need to enter the nucleus of the host and is able to replicate in the cytoplasm or other compartment of the host. The polynucleotide may comprise one or more genomic nucleic acid components, or fragments thereof. The genomic nucleic acid component may comprise a subgenomic nucleic acid or a duplicated subgenomic nucleic acid.

[0066] The polynucleotide may or may not be encapsidated by coat protein(s) encoded by the recombinant virus. The polynucleotide may or may not comprise individual features common to certain viruses, such as a cap at the 5′ terminus of the nucleic acid, a specific initial sequence, or a highly conserved 3′ terminus of the nucleic acid. A cap may comprise a 7-methylguanosine cap. A specific initial sequence may comprise an initial sequence of m⁷ GpppGUA. A highly conserved 3′ terminus may comprise a polyadenylate (poly A) sequence that separates the coding region from a 238 nucleotide 3′ terminal tRNA-like structure. The tRNA-like structure may be able to be aminoacylated with tyrosine. The recombinant viral nucleic acid or recombinant virus is used to infect a host. The recombinant nucleic acid is capable of replication in the host, localized or systemic spread in the host, and transcription or expression of the native nucleic acid in the host to express the fusion protein in the host.

[0067] The fusion protein product may be cleaved by cellular enzymes to free the desired protein, whether it is a protein of interest of an inhibitor of a protease. Alternatively, the fusion protein may be used by itself as the desired product due to having both activities. For example, a protein of interest may employ a protease inhibitor fused with it as a way for blocking cleavage by the protease by stearic inhibition or by having the inhibitor portion acting on the protease itself. Fusion proteins may also have the added advantage of imparting greater storage stability to a protein of interest.

[0068] When the protein of interest is a diagnostic, pharmaceutical, or other directly used protein, a fused protein construct of the protein of interest and another polypeptide may also be used in the same manner. The other polypeptide may be an inhibitor of protease activity or another stabilizer if so desired. Particularly preferred are the use of cleavable linkers, which free the protein of interest before or during use of the protein of interest.

[0069] The polynucleotides of the subject invention may be encoded in RNA or DNA or any synthetic nucleic acid, ss or ds, linear or circular, capable of direct or indirect expression into RNA in a eukaryotic host, such as a yeast, such as Sacchromyces cerevisiae, or a prokaryotic host, such as a bacteria, for example Escherichia coli. Depending on the desired host to be used the necessary nucleotide structures necessary for maintenance in the host, such as origin of replication sites, amplifiable selectable markers, etc., and expression in the host, such as promoters, activation sites, etc. need to be present on the RNA or DNA. Such are known to one of ordinary skill in the art (see Old and Primrose, Principles of Gene Manipulation 5th ed., Blackwell Science, Oxford, U.K. (1994) (Old and Primrose, 1994)).

[0070] A large number of different vectors and techniques may be used for the present invention. These vectors and techniques are well known per se. The present specification, has focused on viral vectors because of their convenience with plants. However other vectors such as Ti plasmids, transposons, etc. may be used.

[0071] Viral vectors into which libraries of genomic or cDNA inserts or sequence variants are inserted may be constructed using a variety of methods known in the art. In preferred embodiments of the instant invention, the viral vectors used to bear such libraries are derived from RNA plant viruses. A variety of plant virus families may be used, such as Bromoviridae, Bunyaviridae, Comoviridae, Geminiviridae, Potyviridae, and Tombusviridae, among others. Within the plant virus families, various genera of viruses may be suitable for the instant invention, such as alfamovirus, ilarvirus, bromovirus, cucumovirus, tospovirus, carlavirus, caulimovirus, closterovirus, comovirus, nepovirus, dianthovirus, furovirus, hordeivirus, luteovirus, necrovirus, potexvirus, potyvirus, rymovirus, bymovirus, oryzavirus, sobemovirus, tobamovirus, tobravirus, carmovirus, tombusvirus, tymovirus, umbravirusa, and among others.

[0072] Within the genera of plant viruses, many species are particular preferred. They include alfalfa mosaic virus, tobacco streak virus, brome mosaic virus, broad bean mottle virus, cowpea chlorotic mottle virus, cucumber mosaic virus, tomato spotted wilt virus, carnation latent virus, cauliflower mosaic virus, beet yellows virus, cowpea mosaic virus, tobacco ringspot virus, carnation ringspot virus, soil-borne wheat mosaic virus, tomato golden mosaic virus, cassaya latent virus, barley stripe mosaic virus, barley yellow dwarf virus, tobacco necrosis virus, tobacco etch virus, potato virus X, potato virus Y, rice necrosis virus, ryegrass mosaic virus, barley yellow mosaic virus, rice ragged stunt virus, Southern bean mosaic virus, tobacco mosaic virus, ribgrass mosaic virus, cucumber green mottle mosaic virus watermelon strain, oat mosaic virus, tobacco rattle virus, carnation mottle virus, tomato bushy stunt virus, turnip yellow mosaic virus, carrot mottle virus, among others. In addition, RNA satellite viruses, such as tobacco necrosis satellite may also be employed.

[0073] A given plant virus may contain either DNA or RNA, which may be either ss or ds. One example of plant viruses containing ds DNA includes, but not limited to, caulimoviruses such as cauliflower mosaic virus (“CaMV”). Representative plant viruses, which contain ss DNA, are cassaya latent virus, bean golden mosaic virus (“BGMV”), and chloris striate mosaic virus. Rice dwarf virus and wound tumor virus are examples of ds RNA plant viruses. ss RNA plant viruses include tobacco mosaic virus (“TMV”), turnip yellow mosaic virus (“TYMV”), rice necrosis virus (“RNV”), brome mosaic virus (“BMV”), and barley stripe mosaic virus (“BSMV”). The ss RNA viruses can be further divided into plus sense (or positive-stranded), minus sense (or negative-stranded), or ambisense viruses. The genomic RNA of a plus sense RNA virus is messenger sense, which makes the naked RNA infectious. Many plant viruses belong to the family of plus sense RNA viruses. They include, for example, TMV, BMV, BSMV, and others. RNA plant viruses typically encode several common proteins, such as replicase/polymerase proteins essential for viral replication and mRNA synthesis, coat proteins providing protective shells for the extracellular passage, and other proteins required for the cell-to-cell movement, systemic infection and self-assembly of viruses. For general information concerning plant viruses, see Hull, R., Matthews' Plant Virology, 4^(th) Ed., Academic Press, San Diego (2002)(Hull, 2002). The viral genome of the virus can be monopartite (such as tobamovirus), or multipartite, including but not limited to bipartite (such as tobravirus) or tripartite (such as hordeivirus).

[0074] Selected groups of suitable plant viruses are characterized below. However, the invention should not be construed as limited to using these particular viruses, but rather the method of the present invention is contemplated to include all plant viruses at a minimum.

Tobamovirus Group

[0075] TMV is a member of the tobamoviruses. The TMV virion is a tubular filament, and comprises coat protein sub-units arranged in a single right-handed helix with the ss RNA intercalated between the turns of the helix. TMV infects tobacco as well as other plants. TMV is transmitted mechanically and may remain infective for a year or more in soil or dried leaf tissue. The TMV virions may be inactivated by subjection to an environment with a pH of less than 3 or greater than 8, or by formaldehyde or iodine. Preparations of TMV may be obtained from plant tissues by (NH₄)₂SO₄ precipitation, followed by differential centrifugation.

[0076] TMV is a positive-stranded ssRNA virus whose genome is 6395 nucleotides long and is capped at the 5′-end but not polyadenylated. The genomic RNA contains a short 5′ NTR followed by an ORF of 4848 nucleotides, which includes an amber stop codon at nucleotide 3417. Two non-structural proteins are expressed from this ORF. The first is a 126 kDa protein (130K) containing the nucleotide binding and putative helicase activities. The second is a 183 kDa protein (180K), which is a translational readthrough of the amber stop codon in about 5-10% of the translational events. The 183 kDa protein contains the functional domains of the 126 kDa protein and a novel domain with homology to RNA-dependent RNA polymerases. At least two subgenomic mRNAs with a common 3′ terminus are also produced after TMV infection. These encode a 30 kDa movement protein and a 17.5 kDa coat protein. The 3′ terminus of TMV genomic RNA can be folded into a series of pseudoknots followed by a tRNA-like structure. The genomic RNA cannot function as a messenger for the synthesis of coat protein. Other genes are expressed during infection by the formation of monocistronic, 3′-coterminal subgenomic mRNAs, including one (LMC) encoding the 17.5K coat protein and another (I₂) encoding a 30K protein. The 30K protein has been detected in infected protoplasts as described in (Miller, 1984), and it is involved in the cell-to-cell transport of the virus in an infected plant as described by (Deom, 1987). The functions of the two large proteins are unknown, however, they are thought to function in RNA replication and transcription.

[0077] Several ds RNA molecules, including ds RNAs corresponding to the genomic, 12 and LMC RNAs, have been detected in plant tissues infected with TMV. These RNA molecules are presumably intermediates in genome replication and/or mRNA synthesis processes, which appear to occur by different mechanisms.

[0078] TMV assembly apparently occurs in plant cell cytoplasm, although it has been suggested that some TMV assembly may occur in chloroplasts since transcripts of ctDNA have been detected in purified TMV virions. Initiation of TMV assembly occurs by interaction between ring-shaped aggregates (“discs”) of coat protein (each disc consisting of two layers of 17 subunits) and a unique internal nucleation site in the RNA; a hairpin region about 900 nucleotides from the 3′-end in the common strain of TMV. Any RNA, including subgenomic RNAs containing this site, may be packaged into virions. The discs apparently assume a helical form on interaction with the RNA, and assembly (elongation) then proceeds in both directions (but much more rapidly in the 3′- to 5′-direction from the nucleation site).

[0079] Another member of the Tobamoviruses, the Cucumber Green Mottle Mosaic virus watermelon strain (“CGMMV-W”) is related to the cucumber virus (Nozu et al., 1971). The coat protein of CGMMV-W interacts with RNA of both TMV and CGMMV to assemble viral particles in vitro (Kurisu et al., 1976).

[0080] Several strains of the tobamovirus group are divided into two subgroups, on the basis of the location of the origin of assembly. Subgroup I, which includes the vulgare, OM, and tomato strain, has an origin of assembly about 800-1000 nucleotides from the 3′-end of the RNA genome, and outside the coat protein cistron (Lebeurier, Nicolaieff, and Richards, 1977); and (Fukuda, 1980). Subgroup II, which includes CGMMV-W and cowpea strain (Cc) has an origin of assembly about 300-500 nucleotides from the 3′-end of the RNA genome and within the coat protein cistron. The coat protein cistron of CGMMV-W is located at nucleotides 176-661 from the 3′-end. The 3′ noncoding region is 175 nucleotides long. The origin of assembly is positioned within the coat protein cistron (Meshi, 1983).

Brome Mosaic Virus Group

[0081] BMV is a member of a group of tripartite, ss, RNA-containing plant viruses commonly referred to as the bromoviruses. Each member of the bromoviruses infects a narrow range of plants. Mechanical transmission of bromoviruses occurs readily, and some members are transmitted by beetles. In addition to BMV, other bromoviruses include broad bean mottle virus and cowpea chlorotic mottle virus.

[0082] Typically, a bromovirus virion is icosahedral, with a diameter of about 26 μm, containing a single species of coat protein. The bromovirus genome has three molecules of linear, positive-sense, ss RNA, and the coat protein mRNA is also encapsidated. The RNAs each have a capped 5′-end, and a tRNA-like structure (which accepts tyrosine) at the 3′-end. Virus assembly occurs in the cytoplasm. The complete nucleotide sequence of BMV has been identified and characterized as described by (Ahlquist, Luckow, and Kaesberg, 1981).

Hordeivirus Group

[0083] Hordeiviruses are a group of ss, positive sense RNA-containing plant viruses with three or four part genomes. Hordeiviruses have rigid, rod-shaped virions. Hordeivirus is composed of four members: BSMV, poa semilatent virus (“PSLV”), lychnis ringspot virus (“LRSV”), and anthoxanthum latent blanching virus (“ALBV”) (Jackson, et al., 1989). BSMV is the type member of this group of viruses. BSMV infects a large number of monocot and dicot species including barley, oat, wheat, corn, rice, spinach, and N. benthamiana. Local lesion hosts include Chenopodium amaranticolor, and Nicotiana tabacum cv. Samsun. BSMV is not vector transmitted but is mechanically transmissible and in some hosts, such as barley, is also transmitted through pollen and seed. Most strains of BSMV have three genomic RNAs referred to as RNAα (or αRNA), RNAβ (or βRNA), and RNAγ (or γRNA). At least one strain, the Argentina mild (AM) strain has a fourth genomic RNA that is essentially a deletion mutant of the RNAγ. All genomic RNAs are capped at the 5′ end and have tRNA-like structures at the 3′ end. Virus replication and assembly occurs in the cytoplasm. The complete nucleotide sequence of several strains of BSMV has been identified and characterized (reviewed by Jackson, et al., 1989), and infectious cDNA clones are available (Petty et al., 1989).

[0084] BSMV is a plus-sense ss RNA virus that is able to infect plants of the Chenopodiaceae, Gramineae, and Solanaceae families, including, but not limited to, the following species: Anthoxanthum aristatum, Anthoxanthum odoratum, Avena sativa, Beta vulgaris, Bromus secalinus, Bromus tectorum, Chenopodium album, Chenopodium amaranticolor, Chenopodium quinoa, Dactylis glomerata, Echinochloa crus-galli, Elytrigia intermedia, Eragrostis cilianensis, Festuca pratensis, Hordeum vulgare, Lagurus ovatus, Lolium multiflorum, Lolium perenne, Lolium persicum, Lolium temulentum, Lophopyrum elongatum, Nicotiana tabacum, Oryza sativa, Oryzopsis miliacea, Panicum capillare, Panicum miliaceum, Phalaris arundinacea, Phalaris paradoxa, Phleum arenarium, Phleum pratense, Poa annua, Poa pratensis, Secale cereale, Setaria italica, Setaria macrostachya, Setaria viridis, Sorghum bicolor, Spinacia oleracea, Triticum aestivum, Triticum durum, and Zea mays. The method of transmission does not involve a vector and is by mechanical inoculation by seed (up to 90-100%) and by pollen to the pollinated plant. BSMV virions are rod-shaped, not enveloped, and usually straight. (Brunt et al., Plant Viruses Online: Descriptions and Lists from the VIDE Database, URL http://biology.anu.edu.au/Grouops/MES/vide/, 1996 onwards).

[0085] The BSMV virion contains 3.8-4% nucleic acid, 96% protein, and 0% lipid by weight. The BSMV genome consists of three ss linear RNA (designated RNAα, RNAβ, and RNAγ). The total genome size is 10.289 kb (Brunt et al., 1996). Each genomic RNA has a 7-methylguanosine cap at its 5′ terminus and contains the initial sequence m⁷ GpppGUA, and has a highly conserved 3′ terminus that has a polyadenylate (poly A) sequence that separates the coding region of each RNA from a 238 nucleotide 3′ terminal tRNA-like structure that can be aminoacylated with tyrosine. BSMV encodes a total of seven polypeptides. RNAα encodes αa, a 130 kDa protein which is believed to be an integral component of viral replicase. αa has a putative methyltransferase domain near the N-terminus and a nucleotide binding motif near the C-terminus (Jackson et al., 1991). When αa of BSMV strain N18 (non-pathogenic to oat) had more than half of its ORF replaced with the homologous αa of BSMV strain CV42 (pathogenic to oat), the gene homologous gene replacement enabled strain N18 to infect oat. In addition, a single amino acid substitution or up to six single amino acid substitutions (including the substitution of two adjacent amino acids) in αa of strain N18 enabled strain N18 to infect oat (Weiland and Edwards, 1996). RNAβ encodes four polypeptides: βa, the 22 kDa coat protein; βb, a 60 kDa disease-specific protein, which contains a nucleotide binding motif similar to αa; βc, a 17 kDa protein of unknown function but which is required for infectivity in barley (N. benthamiana and C. amaranticolor); and, βd, a 14 kDa protein essential for systemic infection and associated with the membrane fraction of infected barley. The ORFs of βb, βc and βd are tightly organized to form a triple gene block (“TGB”) whereby βd overlaps βb and βc. The TGB is similar in organization to the overlapping gene blocks found in furoviruses, potexviruses, and potato virus M, a carlavirus (Jackson et al., 1991). RNAγ encodes two ORFs: γa and γb. The γa ORF encodes a second replicase component, γa, that contains the GDD polymerase motif that is universally present in the replicases of plus-sense RNA viruses. The γb ORF encodes a 17 kDa cysteine rich protein, γb, contains a cysteine-rich region. BSMV with mutations that introduce single or up to four single amino acid substitutions in γb, when used to inoculate barley plants, resulted in altered symptom phenotype (Donald and Jackson, 1994). BSMV is of interest to provide new and improved vectors for the genetic manipulation of plants.

Rice Necrosis Virus

[0086] RNV is a member of the Potato Virus Y Group or Potyviruses. The Rice Necrosis virion is a flexuous filament comprising one type of coat protein (molecular weight about 32,000 to about 36,000) and one molecule of linear positive-sense ss RNA. The Rice Necrosis virus is transmitted by Polymyxa oraminis (a eukaryotic intracellular parasite found in plants, algae and fungi).

Geminiviruses

[0087] Geminiviruses are a group of small, ss DNA-containing plant viruses with virions of unique morphology. Each virion consists of a pair of isometric particles (incomplete icosahedral), composed of a single type of protein (with a molecular weight of about 2.7-3.4×10⁴). Each geminivirus virion contains one molecule of circular, positive-sense, ss DNA. In some geminiviruses (i.e., Cassaya latent virus and bean golden mosaic virus) the genome appears to be bipartite, containing two ss DNA molecules.

Potyviruses

[0088] Potyviruses are a group of plant viruses, which produce polyprotein. A particularly preferred potyvirus is tobacco etch virus (“TEV”). TEV is a well characterized potyvirus and contains a positive-strand RNA genome of 9.5 kilobases encoding for a single, large polyprotein that is processed by three virus-specific proteinases. The nuclear inclusion protein “a” proteinase is involved in the maturation of several replication-associated proteins and capsid protein. The helper component-proteinase (HC-Pro) and 35-kDa proteinase both catalyze cleavage only at their respective C-termini. The proteolytic domain in each of these proteins is located near the C-terminus. The 35-kDa proteinase and HC-Pro derive from the N-terminal region of the TEV polyprotein.

[0089] The selection of the genetic backbone for the viral vectors of the instant invention may depend on the plant host used. The plant host may be a monocotyledonous or dicotyledonous plant, plant tissue, plant organ, or plant cell. Typically, plants of commercial interest, such as food crops, seed crops, oil crops, ornamental crops and forestry crops are preferred. For example, wheat, rice, corn, potato, barley, tobacco, soybean canola, maize, oilseed rape, lilies, grasses, orchids, irises, onions, palms, tomato, the legumes, or Arabidopsis, can be used as a plant host. Host plants may also include those readily infected by an infectious virus, such as Nicotiana, preferably, Nicotiana benthamiana, or Nicotiana clevelandii.

[0090] The source of the protein of interest and nucleic acid encoding the protein of interest can be derived or obtained from one or more donor organisms. The donor organism may be any organism of any classification, which includes Kingdom Monera, Kingdom Protista, Kingdom Fungi, Kingdom Plantae and Kingdom Animalia. Kingdom Monera includes subkingdom Archaebacteriobionta (archaebacteria): division Archaebacteriophyta (methane, salt and sulfolobus bacteria); subkingdom Eubacteriobionta (true bacteria): division Eubacteriophyta; subkingdom Viroids; and subkingdom Viruses. Kingdom Protista includes subkingdom Phycobionta: division Xanthophyta (yellow-green algae), division Chrysophyta (golden-brown algae), division Dinophyta (Pyrrhophyta) (dinoflagellates), division Bacillariophyta (diatoms), division Cryptophyta (cryptophytes), division Haptophyta (haptonema organisms), division Euglenophyta (euglenoids), division Chlorophyta, class Chlorophyceae (green algae), class Charophyceae (stoneworts), division Phaeophyta (brown algae), and division Rhodophyta (red algae); subkingdom Mastigobionta: division Chytridiomycota (chytrids), and division Oomycota (water molds); subkingdom Myxobionta: division Acrasiomycota (cellular slime molds), and division Myxomycota (true slime molds). Kingdom Fungi includes division Zygomycota (coenocytic fingi): subdivision Zygomycotina; and division Eumycota (septate fungi): subdivision Ascomycotina 000 (cup fungi), subdivision Basidiomycotina (club fungi), subdivision Deuteromycotina (imperfect fungi), and subdivision Lichenes. Kingdom Plantae includes division Bryophyta, Hepatophyta, Anthocerophyta, Psilophyta, Lycophyta, Sphenophyta, Pterophyta, Coniferophyta, Cycadeophyta, Ginkgophyta, Gnetophyta and Anthophyta. Kingdom Animalia includes: Porifera (Sponges), Cnidaria (Jellyfishes), Ctenophora (Comb Jellies), Platyhelminthes (Flatworms), Nemertea (Proboscis Worms), Rotifera (Rotifers), Nematoda (Roundworms), Mollusca (Snails, Clams, Squid & Octopus), Onychophora (Velvet Worms), Annelida (Segmented Worms), Arthropoda (Spiders & Insects), Phoronida, Bryozoa (Bryozoans), Brachiopoda (Lamp Shells), Echinodermata (Sea Urchins & starfish), and Chordata (Vertebrata-Fish, Birds, Reptiles, Mammals). A preferred donor organism is human. The donor organism may be any virus.

[0091] There can be one or more polynucleotides. The protein of interest may be encoded and expressed from one or a first polynucleotide and the genetic element capable of reducing a protease activity may be on another or second polynucleotide.

[0092] The protein of interest may be present in only certain tissue(s) or region(s) of the host. As such, the responsible agent of reducing protease activity should be active in the same tissue(s) or region(s). Tissue specific expression is known in a number of host parts such as plant seeds (Batchelor et al., 2000; Tanaka et al., 2001; Yamagata et al., 2000), leaves (Jorda et al., 1999; Meichtry, Amrhein, and Schaller, 1999), roots (Jorda, Conejero, and Vera, 2000; Meichtry, Amrhein, and Schaller, 1999) and as mentioned above.

[0093] Expression of a plant subtilisin-like protease has also been proposed in the regulation of stomatal distribution and density in Arabidopsis thaliana (Berger and Altmann, 2000a; Berger and Altmann, 2000b). Thus, reducing its activity for such purposes is also a use for the present invention.

[0094] The viral vector can also be a monopartite tobravirus RNA-1 comprising an inserted foreign RNA sequence operably linked to the 3′-end of the stop codon of the RNA sequence that codes for a 16 kDa cysteine-rich protein of RNA-1. The host can be any cell capable of expressing the protein of interest and/or the genetic element capable of reducing a protease activity. The host can be any plant cell. The plant cell may a protoplast, a recombinant cell, a transgenic cell, a non-transgenic cell, or a cell that is part of a cell culture, cell tissue, plant organ, or an entire plant organism. A protoplast is a plant cell that has the cell wall removed. The plant cell can be a dicot or a monocot plant cell. Preferably, the plant cell is a dicot plant cell. More preferably, the dicot plant cell is a Nicotiana benthamiana cell. The host may be of a species or strain that can be infected with a viral genome or a recombinant virus obtained from a virus that can infect the host.

[0095] Plant hosts include plants of commercial interest, such as food crops, seed crops, oil crops, ornamental crops and forestry crops. For example, wheat, rice, corn, potatoes, barley, tobaccos, soybean canola, maize, oilseed rape, Nicotiana sp. can be selected as a host plant. Plants without commercial interest may also be used, for example, Arabidopsis sp. In particular, host plants capable of being infected by a virus containing a recombinant viral nucleic acid are preferred. Preferred host plants include Nicotiana. More preferably, the host plants are N. benthamiana, N. excelsiana, N. clevelandii or tobacco.

[0096] Individual clones may be transfected into the plant host, such as (1) protoplasts; (2) cell or tissue cultures, (3) whole plants; or (4) plant tissues, such as leaves of plants (Dijkstra, 1998; Foster and Taylor, 1998). In some embodiments of the instant invention, the delivery of the recombinant plant nucleic acid into the plant may be affected by the inoculation of in vitro transcribed RNA, inoculation of virions, or internal inoculation of plant cells from nuclear cDNA, or the systemic infection resulting from any of these procedures. In all cases, the co-infection may lead to a rapid and pervasive systemic expression of the desired nucleic acid sequences in plant cells.

[0097] The host can be infected with a recombinant viral nucleic acid or a recombinant plant virus by conventional techniques. Suitable techniques include, but are not limited to, leaf abrasion, abrasion in solution, high velocity water spray, and other injury of a host as well as imbibing host seeds with water containing the recombinant viral RNA or recombinant plant virus. More specifically, suitable techniques include:

[0098] (a) Hand Inoculations. Hand inoculations are performed using a neutral pH, low molarity phosphate buffer, with the addition of a particulate such as celite or carborundum (usually about 1%). One to four drops of the preparation is put onto the upper surface of a leaf and gently rubbed.

[0099] (b) Mechanized Inoculations of Plant Beds. Plant bed inoculations are performed by spraying (gas-propelled) the vector solution into a tractor-driven mower while cutting the leaves. Alternatively, the plant bed is mowed and the vector solution sprayed immediately onto the cut leaves.

[0100] (c) High Pressure Spray of Single Leaves. Single plant inoculations can also be performed by spraying the leaves with a narrow, directed spray (50 psi, 6-12 inches from the leaf) containing approximately 1% carborundum in the buffered vector solution.

[0101] (d) Vacuum Infiltration. Inoculations may be accomplished by subjecting a host organism to a substantially vacuum pressure environment in order to facilitate infection.

[0102] (e) High Speed Robotics Inoculation. Especially applicable when the organism is a plant, individual organisms may be grown in mass array such as in microtiter plates. Machinery such as robotics may then be used to transfer the nucleic acid of interest.

[0103] (f) Ballistics (High Pressure Gun) Inoculation. Single plant inoculations can also be performed by particle bombardment. A ballistics particle delivery system (BioRad Laboratories, Hercules, (A) can be used to transfect plants such as N. benthamiana as described previously (Nagar et al., 1995).

[0104] An alternative method for introducing recombinant viral nucleic acids into a plant host is a technique known as agroinfection or Agrobacterium-mediated transformation (also known as Agro-infection) as described by (Grimsley, 1987). This technique makes use of a common feature of Agrobacterium, which colonizes plants by transferring a portion of their DNA (the T-DNA) into a host cell, where it becomes integrated into nuclear DNA. The T-DNA is defined by border sequences that are 25 base pairs long, and any DNA between these border sequences is transferred to the plant cells as well. The insertion of a recombinant plant viral nucleic acid between the T-DNA border sequences results in transfer of the recombinant plant viral nucleic acid to the plant cells, where the recombinant plant viral nucleic acid is replicated, and then spreads systemically through the plant. Agro-infection has been accomplished with potato spindle tuber viroid (PSTV) (Gardner, 1986); CaV (Grimsley, 1986); MSV (Grimsley, 1987), and (Lazarowitz, 1988)) digitaria streak virus (Donson et al., 1988), wheat dwarf virus (Hayes, 1988) and tomato golden mosaic virus (TGMV) (Elmer, 1988) and (Gardiner, 1988). Therefore, agro-infection of a susceptible plant could be accomplished with a virion containing a recombinant plant viral nucleic acid based on the nucleotide sequence of any of the above viruses. Particle bombardment or electroporation or any other methods known in the art may also be used.

[0105] In some embodiments of the instant invention, infection may also be attained by placing a selected nucleic acid sequence into an organism such as E. coli, or yeast, either integrated into the genome of such organism or not, and then applying the organism to the surface of the host organism. Such a mechanism may thereby produce secondary transfer of the selected nucleic acid sequence into a host organism. This is a particularly practical embodiment when the host organism is a plant. Likewise, infection may be attained by first packaging a selected nucleic acid sequence in a pseudovirus. Such a method is described in U.S. Pat. No. 5,443,969 (Wilson and Hwang-Lee, 1995). Though the teachings of this reference may be specific for bacteria, those of ordinary skill in the art will readily appreciate that the same procedures could easily be adapted to other organisms.

[0106] Plant may be grown from seed in a mixture of “Peat-Lite Mix™” (Speedling, Inc. Sun City, Fla.) and Nutricote™ controlled release fertilizer 14-14-14 (Chiss-Asahi Fertilizer Co., Tokyo, Japan). Plants may be grown in a controlled environment provided 16 hours of light and 8 hours of darkness. Sylvania “Gro-Lux/Aquarium” wide spectrum 40 watt fluorescent grow lights (Osram Sylvania Products, Inc. Danvers, Mass.) may be used. Temperatures may be kept at around 27° C. during light hours and 21° C. during dark hours. Humidity may be between 60 and 85%.

[0107] In the examples below, we describe the purification and characterization of novel Nicotiana benthamiana plant proteases that are involved in the cleavage of a mammalian therapeutic protein in vitro and in vivo. Based on molecular, biochemical and functional properties, these enzymes are classified as subtilisin-like serine proteases and named Nicotianalisins. In addition, we describe a method used to clone two members of the N. benthamiana subtilisin-like protease gene family. This method utilizes the parameters of strict conservation of the catalytic triad domain in this family of proteases and can be used to clone similar proteases from other species of plants. These examples also describe the isolation of thirteen other members of the N. benthamiana subtilisin-like protease gene family from a sequenced and annotated N. benthamiana library using databases searching tools. Molecular approaches to down regulating the activity of this protease activity in vivo as a means to produce human therapeutics in plants are also described.

[0108] Cloning of the Nicotianalisin genes allowed the development of methods to reduce Nicotianalisin protease activity in order to decrease the proteolysis of recombinant proteins expressed in the plant. Expression of the cloned Nicotianalisin gene may be performed to produce even higher amounts of the protease, which may be purified and used as a product per se in purified or essentially isolated form.

[0109] When the protease-labile protein of interest is native to the host cell, one need only inhibit the proteases in order to increase effective recovery of the protein of interest. The present invention using a vector with the genetic element may be used to increase the recovery of that protein of interest. This and similar methods are particularly effective when recovering proteins from the interstitial fluid which contains endogenous protease. A number of protease inhibitors are known to be secreted extracellularly (Horisberger et al, Histochemistry. 1983;77(3):313-21) and such are preferred.

[0110] The following examples further illustrate the present invention. While the examples show reducing one protease activity, the same techniques may simultaneously reduce plural protease activities; for example, by using a non-specific protease inhibitor or plural genetic elements, each specific for different protease activities. These examples are intended merely to be illustrative of the present invention and are not to be construed as being limiting.

[0111] Throughout the specification, the emphasis has been on reducing protease activity. However, other biological activities are present inside a cell, which may degrade the protein of interest. These include other hydrolases acting on ester, amide or glucosidic, cyclic amides (e.g. beta-lactamase), isomerases, asparginases, saccharidase, nuclease and small organic molecule cleaving enzymes. For example, a saccharidase may alter (or even completely remove) the glycosylation pattern of the protein of interest. Inhibition of these enzymes are also contemplated as part of the present invention.

EXAMPLES Example 1

[0112] Purification and Biochemical Characterization of Nicotiana benthamiana Subtilisin-Like Serine Protease.

[0113] Initial Characterization of Protease Activity

[0114] When a plant viral vector expression system (Kumagai et al., 1995; McCormick et al., 1999) was utilized to express the secreted, mammalian recombinant protein, hGH, significant degradation of the target protein was observed. Experiments were performed to identify the proteolytic activity responsible for the degradation. N. benthamiana plants were grown in a controlled environment with 27° C. day and 23° C. night temperatures, a 12 hour photoperiod, and 86% relative humidity. Plants were inoculated three weeks post sow date with infectious transcripts of a plant viral vector comprising an hGH gene sequence in-frame with a tobacco extensin signal peptide as previously described for other tobamovirus expression studies (Kumagai et al., 1995; McCormick et al., 1999). Eight to ten days post-inoculation (dpi), virally-infected plant material was harvested and used for isolation of the plant interstitial fluid (IF) as previously described (McCormick et al., 1999).

[0115] Aliquots of the plant IF fraction were separated by SDS-PAGE and levels of hGH protein were detected by immunoblot analysis using anti-hGH polyclonal antibody (Sigma, St. Louis, Mo.). Briefly, proteins were separated on precast gels with an Xcell II Mini-Cell apparatus (Invitrogen, Carlsbad, Calif.) in the buffer system of Laemmli (Laemmli, 1970). Proteins were electrophoretically transferred (1 hr, 100 volts, 4° C.) to a nitrocellulose membrane (0.45 μm)(Schleicher and Schuell, Dassel, Germany). After blocking of nonspecific binding sites with 5% non-fat dried milk in Tween 20/Tris-HCl buffered Saline (TBST) for 2 hr, the blot was incubated for 2 hr with a 1:1000 dilution of anti-hGH antibody. Blots were developed using goat-anti-rabbit alkaline phosphatase-conjugated secondary antibodies (Sigma) as per manufacturer's instructions.

[0116]FIG. 1 reveals the inhibitory effects observed using specific protease inhibitors against the plant protease. At zero time, prior to the addition of any inhibitors, both full length and hGH cleavage products were detected (FIG. 1). When chymostatin, a specific inhibitor of chymotrypsin- and subtilisin- like proteases (Umezawa, 1976), was added to the IF extract, the inhibition of further degradation of the intact hGH protein was observed. The addition of potato protease inhibitor I (PI-I), a specific inhibitor of chymotrypsin-like serine protease activity (Plunkett et al., 1982), also inhibited degradation of the recombinant protein, but not as well as chymostatin. In the absence of any protease inhibitor, the full-length hGH protein was completely degraded in the plant IF extract.

[0117] Plant Protease Inhibitor Studies

[0118] To further classify the protease activity in the plant IF extract, protease inhibitor studies were performed. Standard inhibitors from different classes of proteases were used. An aliquot of the plant IF was incubated with each inhibitor for 30 min at 24° C., and the free enzyme was incubated under the same conditions without the inhibitor to serve as the control. The protease activity after the inhibition was measured and compared to the control. The results of this study, and the specifications of each inhibitor (Twining, 1984), are summarized in Table 1. Protease inhibitors that specifically target the class of serine proteases exhibited 100% inhibition of protease activity in an in vitro assay. Interestingly, approximately 40% inhibition was observed when inhibitors of either chymotrypsin-like proteases or elastases were used. TABLE 1 Nicotianalisin inhibition in the presence of inhibitors from different classes of proteases. IF was prepared from viral vector-infected plants and incubated with each inhibitor for 30 min at 24° C. Protease activity following inhibitor treatment was measured using 0.3 mM N-Suc-AAPL-p-NA (see below). Reduction of the protease activity was reported as percent inhibition compared to the activity in the IF from an uninfected plant (control). % No. Inhibitor Inhibition Class Comments 1 Control 0 Serine/Irr* 2 3-4 DCI 100 Serine/Irr Fast inhibitor 3 PMSF 100 Serine/Irr 4 Chymostatin 100 Serine/Irr 5 TLCK 0 Serine/Irr Trypsin-like 6 TPCK 38 Serine/Irr Chymotrypsin-like 7 N-CBZ-GGF-CK 70 Serine/Irr Active site titrant 8 pI-I 30 Serine Chymotrypsin-like 9 pI-II 2 Serine Trypsin-like 10 Trypsin-Chymo I 55 Serine Trypsin/ chymotrypsin 11 Aprotinin 46 Serine/Rev* 12 Elastinal 41 Serine/Rev Elastase-like 13 Antipain 77 Serine/ Trypsin and Cysteine many cysteine-like 14 Leupeptin 18 Ser/Cysteine Trypsin and many cysteine-like 15 E-64 5 Cysteine/Irr Active site titrant 16 Cystain 2 Cysteine/Rev 17 EDTA 5 Metallo/Rev Chelator 18 Amastatin 5 Metallo/Rev Aminopeptidase I 19 1-10 Phenantrolin 11 Metallo/Rev Chelator 20 Pepstatin A 6 Aspartic/Rev

[0119] No. 7 has SEQ ID NO:

[0120] A large number of other protease inhibitors may be used. Particularly preferred are polypeptide protease inhibitors, which may be co-expressed with the protein of interest. For example, apolipoprotein A-I, tissue inhibitors of matrix metalloproteinases (MMPs), serine protease inhibitor, soybean trypsin inhibitor, soybean and other cysteine protease inhibitor, soyacystatin N (scN), winged bean chymotrypsin inhibitor, tomato protease inhibitor, etc.

[0121] Plant Protease Enzyme Assays

[0122] To further characterize the plant proteolytic activity, experiments were initiated to partially purify the plant protease. In order to purify the protease, enzyme assays were developed and utilized. Proteolytic activity was monitored by the hydrolysis of a synthetic substrate, hydrolysis of a protein substrate and/or by an in situ gel procedure. Assays based on synthetic substrates were performed in 100 mM Tris-HCl, pH 7.0, 5 mM CaCl₂ for 30 min at 37° C. The synthetic substrate was N-Succinyl-Alanine-Alanine-Proline-Leucine-para-nitroanilide (N-Suc-Ala-Ala-Pro-Leu-p-NA SEQ ID NO:) and/or N-Succinyl-Alanine-Alanine-Proline-Phenylalanine-para-nitroanilide (N-Suc-Ala-Ala-Pro-Phe-p-NA SEQ ID NO:) at 0.3 mM final concentration (Largman et al., 1980; Siekierka et al., 1989). The absorbance of the p-nitroaniline (p-NA) produced was measured at 410 nm (Erlanger, Kokowsky, and Cohen, 1961; Nakajima et al., 1979). The activity unit was defined as the amount of the enzyme capable of producing 1 nanomole of p-NA per min under the conditions of the experiment with an absorption coefficient of 8.8 mM cm⁻¹ (Erlanger, Kokowsky, and Cohen, 1961; Nakajima et al., 1979). The rate of hydrolysis of N-Succinyl-Ala-Ala-Pro-Phe-thiobenzylester SEQ ID NO: in 10% DMSO and 4,4′-dithiodipyridine was monitored at 324 nM using an extinction coefficient of 19800 cm⁻¹ M⁻¹ (Barrett and Kirschke, 1981). General proteolytic activity was measured with 2.0% azocasein or 2.0% azoalbumin and Fluorescein Isothiocyanate Casein (FITC-casein; (Twining, 1984)). The reaction was started by addition of 10 μl of protease solution to 70 μl of reaction mixture (100 mM buffer Tris-HCl pH 7.0 containing 0.04% FTC-casein, 0.5 mM DDT, 2 mM CaCl₂) and incubation for 1 hr at 37° C. The reaction was stopped by addition of 80 μl of 10% TCA and incubation for 15 min at −20° C. The mixture was centrifuged for 10 min at 10,000×g at 4° C. 10 μl of the supernatant solution was added to 150 μl Tris-HCl (0.5 M, pH 8.5), and fluorescence was measured at an excitation wavelength of 490 nm and an emission wavelength of 525 nm using a fluorescence plate reader ((Erlanger, Kokowsky, and Cohen, 1961; Nakajima et al., 1979), Molecular Devices).

[0123] The in situ protease gel assay was carried out in pre-cast 10% Zymogram gels (Invitrogen, Carlsbad, Calif.) as per manufacturer's protocols.

[0124] Partial Purification and Further Characterization of the Plant Protease

[0125] Following the initial observation that the plant protease activity was inhibited by both chymostatin and potato PI-I (FIG. 1), experiments were initiated to partially purify the protease from N. benthamiana leaves. Plants were grown and IF extracts were prepared as described above. The IF was filtered through a 0.8μ Sartorius GF membrane to remove most of the Ribulose-1,5-bisphosphate carboxylase/oxygenase (Rubisco) and green pigments. The diafiltered extract was separated further by SP sepharose (Pharmacia) ion exchange chromatography at pH 5.2. Proteolytic activity from column chromatography fractions was monitored by the hydrolysis of the synthetic substrate, N-Suc-Ala-Ala-Pro-Leu-p-NA SEQ ID NO:, as described above.

[0126] When the partially purified fraction containing highest proteolytic activity was treated with or without phenylmethanesulfonyl fluoride (PMSF) (Sigma), a general serine protease inhibitor (Moss and Fahrney, 1978), a significant reduction of protease activity was observed (FIG. 2). Using the in situ gel protease assay referenced above, a significant inhibition of clearing was observed in the Zymogram gelatin gel. This observation indicates that PMSF is a potent inhibitor of the partially purified plant protease, and therefore, the plant protease belongs to the serine protease family.

[0127] Purification of the Nicotianalisin Enzyme

[0128] In order to fully characterize the plant protease, Nicotianalisin, it was necessary to purify the enzyme. N. benthamiana plants were grown and IF extracts were prepared and diafiltered as described above. Proteolytic activity from column chromatography fractions was monitored by the hydrolysis of synthetic substrates, as described above.

[0129] Clarified IF was concentrated by an ultrafiltration system, using a 10,000 MWCO Amicon spiral membrane (Millipore). The supernatant solution of a 30% ammonium sulfate cut was filtered through a ≧0.2≦0.65μ filter and applied to a Butyl Sepharose (Pharmacia) chromatography column equilibrated with 30% saturated ammonium sulfate in 25 mM imidazole buffer, pH 6.0 (buffer A). Unbound proteins were washed from the column with buffer A, and Nicotianalisin activity was eluted with a linear gradient of decreasing ammonium sulfate in buffer A. Fractions with protease activity were pooled and dialyzed overnight against 25 mM Tris-HCl, pH 7.0 or concentrated and diafiltrated with 25 mM Tris-HCl, pH 7.0 using an ultrafiltration system. The concentrated active pool from Butyl Sepharose was applied to a DEAE Sepharose column equilibrated with 25 mM Tris-HCl, pH 7.0. After washing the unbound proteins from the column, the activity was eluted with a linear NaCl gradient from 0 to 200 mM in the equilibration buffer. Active fractions were collected and concentrated using a BioMax 10,000 MWCO membrane (Millipore), and applied to a Sephacryl S-100 gel filtration column (Pharmacia). The protein was eluted using 50 mM Tris-HCl buffer, pH 7.0, containing 150 mM NaCl. The pooled S-100 fractions were purified further using a Superose-12 (Pharmacia) size exclusion column equilibrated in 50 mM Tris-HCl buffer, pH 7.0, containing 150 mM NaCl. The protein concentration was measured using Bradford protein reagent (Bio-Rad Laboratories, Hercules, Calif.).

[0130] The steps in the purification of Nicotianalisin from the IF of N. benthamiana leaves are summarized in Table 2. Protease activity was retained nearly quantitatively and the activity eluted as a single peak during all column purification steps. Nicotianalisin was purified 306-fold with a specific activity of 3171 units/mg total protein after the final purification step. TABLE 2 Purification of Nicotianalisin from N. benthamiana leaf. Total Total Specific Purification Purification Activity¹ Protein Activity Yield factor Steps units mg units/mg percent fold IF 3306 319 10.4 100.0 1 UF-DF 3046 232 13.1 92.1 1 Butyl 2087 25 83.5 63.1 8 Sepharose DEAE 771 2.2 350.4 23.3 34 Sepharose Sephacryl 414 0.35 1181.5 12.5 114 S-100 Superose-12 203 0.064 3170.9 6.1 306

[0131]FIG. 3 represents an overview of the purification steps analyzed by 14% SDS-PAGE stained with Coomassie brilliant blue. Protein samples of the various purification steps (2.5 μg total protein) were loaded per lane. Enrichment of a protein band with an apparent molecular mass of 80 kD was observed after the final purification step (FIG. 3).

[0132] The protease was also purified using other combinations of column chromatography, such as, SP-Sepharose, isoelectric focusing, and Mono-Q HR. The active fractions from the DEAE column (see table above) were pooled and applied to an isoelectric focusing column. The activity was eluted over a pH range of 7 to 3.5 using polybuffer 74 (Amersham Pharmacia Biotech). The majority of the Nicotianalisin activity was eluted at acidic pH. Different isozymes were also separated using cation exchange chromatography (SP-Sepharose, Mono-S) by loading the column over a pH range of 5.2 to 4.5 and eluting with a linear gradient of 0 to 250 mM NaCl in binding buffer.

[0133] Biochemical Characterization of Purified Nicotianalisin

[0134] Following purification of the plant protease, various biochemical analyses were performed in order to fully characterize the enzyme.

[0135] Nicotianalisin Amino acid Sequence Homologous to Other Plant Subtilisins:

[0136] N-terminal amino acid sequence. An aliquot of the purified Nicotianalisin protein was immobilized on PVDF (ProBlot, Applied Biosystems) membrane and the N-terminal sequence of the mature protein was determined using an Applied Biosystems Sequencer. The N-terminal amino acid sequence of the purified, mature N. benthamiana secreted protease was determined to be TTHTSQFLGL (SEQ ID NO: 30) (FIG. 4). The site of propeptide processing appears to occur amino-terminal to a pair of threonine residues. This sequence is homologous to other plant subtilisin-like proteases (FIG. 4) and contains the conserved motif that has been described in other plant subtilisin-like proteases (Meichtry, Amrhein, and Schaller, 1999).

[0137] Internal amino acid peptide sequence. The amino acid sequence of an internal fragment of the purified protease was determined using electrospray ionization-tandem mass spectrometry (ESI-MS/MS). An aliquot of the purified protein was separated by SDS-PAGE and digested enzymatically in-gel using porcine trypsin following standard protocols. Tryptic peptides were reconstituted in 5% acetonitrile/0.1% formic acid/94.9% water, separated on a C-18 column and analyzed using an Applied Biosystems API-QSTAR™ LC/MS/MS system. Full scan Q1 data was acquired by scanning from 450 to 2200 m/z, charged ions were selected for MS/MS analysis, and instrument software was used to determine the amino acid sequence of selected ions. The following sequence was determined from a tryptic fragment of Nicotianalisin: FGYATGTAIGIAPK (SEQ ID NO: 31). When the resultant sequence was used to search for homologues in an NCBI BLASTp search (Altschul et al., 1997), the top 18 matches producing significant alignments with 61-81% identity, were all to plant subtilisin-like proteases.

[0138] Molecular weight determination: The average molecular mass of the purified protease was determined using matrix-assisted laser/desorption ionization time-of-flight (MALDI-TOF) mass spectrometry using an Applied Biosystem's DE-PRO Biospectrometry™ Workstation. An aliquot of the protease was mixed with an equal volume of 10 mg/ml sinapinic acid (Sigma) matrix solution in 0.1% TFA:acetonitrile (2:1 v/v). The MALDI-TOF MS spectra were acquired at an accelerating voltage of 25 kV and in the positive ion mode.

[0139] The average molecular mass of the purified, mature protease was 78955 Da as determined by MALDI-TOF mass spectrometry. This mass concurs well with other plant subtilisin-like proteases that have been reported (Jorda et al., 1999; Meichtry, Amrhein, and Schaller, 1999; Tornero, Conejero, and Vera, 1996; Yamagata et al., 1994).

[0140] Effect of pH on the activity of purified Nicotianalisin: The purified N. benthamiana protease exhibited activity in a broad pH range with optimal enzyme activity at pH 7-7.5 (FIG. 5). Nicotianalisin was very stable in the pH range of 5.0 to 9.0. The assays were conducted in 0.1 M bis-Tris propane containing 5 mM CaCl₂ at pHs ranging from 6 to 10.5 for 30 min at 37° C. N-Suc-AAPF-pNA SEQ ID NO: (Del Mar et al., 1980; Del Mar et al., 1979) was used as a substrate at 0.3 mM in the reaction mixture as described above. The absorbance of the p-nitroaniline produced was measured at 410 nm. Values are shown as percentages of the maximum activity.

[0141] Nicotianalisin Protease Substrate Specificity:

[0142] Protease-mediated hydrolysis of bovine insulin B chain. An aliquot of the pure protease was mixed with oxidized insulin B chain protein (Sigma) (5 mg/ml) and incubated for 2 to 16 hr at 37° C. The reactions were stopped by addition of 0.1% TFA in 50% acetonitrile and the mass of the cleavage products was determined by MALDI-TOF mass spectrometry as described above. As indicated in FIG. 6, hydrolysis occurred after leucine, cysteine, proline, and lysine amino acid residues. Nicotianalisin protease also showed a preference for large hydrophobic residues in the P₃ and P₄ positions of insulin B-chain with respect to Leu-15, Cys-19, Pro-28, and Lys-29 (FIG. 6). This is a common biochemical characteristic of other plant subtilisin-like proteases (Rudenskaya et al., 1998). Nicotianalisin enzyme specificity. The enzyme specificity of Nicotianalisin was assessed by monitoring the cleavage efficiency of numerous chromogenic synthetic substrates. An aliquot of the purified protease was added to an assay mixture containing 0.1 M Tris-HCl, pH 7.0, 5 mM CaCl₂, 0.5-2.7% dimethylformamide, and 0.3 to 2 mM synthetic substrate and allowed to proceed for 30 min at 37° C. The released p-NA moiety was measured at 410 mu as previously described. Relative activity was reported as a percentage activity of Nicotianalisin in the presence of a given substrate compared to N-Suc-AAPL-pNA SEQ ID NO: substrate at a given substrate concentration.

[0143] As summarized in Table 3, purified Nicotianalisin preferentially cleaved the synthetic peptide substrates N-Suc-Ala-Ala-Pro-Leu-p-NA SEQ ID NO:, N-Suc-Ala-Ala-Pro-Met-p-NA SEQ ID NO:, and N-Suc-Ala-Ala-Pro-Phe-p-NA SEQ ID NO:, after the Leu, Met, and Phe amino acid residues, respectively. This is in close agreement with the activities of other plant subtilisin-like proteases that have been reported (Kaneda, Yonezawa, and Uchikoba, 1995; Rudenskaya et al., 1998; Uchikoba, Yonezawa, and Kaneda, 1995). In general, Nicotianalisin had a strong primary preference for hydrophobic amino acids at scissile bonds and extended peptide substrates. Presence of hydrophobic residues Val and Tyr at P₃ and P₄ positions increased the activity at cleavage sites several fold (Substituent-NH—P₄—P₃—P₂—P₁—P₁′—COO-substituent SEQ ID NO:).

[0144] Table 3. Hydrolysis of homologous synthetic 4-nitroanilide peptides by Nicotianalisin. Enzymatic assays were conducted at 0.3 mM substrate concentration in 0.1 M Tris-HCl, pH 7.0, containing 5 mM CaCl₂, and 0.5-2.7% dimethylformamide at 25° C. Substrate specificity is reported as a percentage of activity of Nicotianalisin in the presence of a given substrate relative to the activity in the presence of N-Suc-AAPL-pNA SEQ ID NO: substrate. Substrate Relative Activity N-Suc-AAPL-pNA 100 SEQ ID NO: N-Suc-AAPM-pNA 100 SEQ ID NO: N-Suc-AAPF-pNA 67 SEQ ID NO: N-Suc-AAPA-pNA 24 SEQ ID NO: N-Suc-AAPV-pNA 8 SEQ ID NO: N-Suc-AAPD-pNA 16 SEQ ID NO: N-Suc-AAVA-pNA 20 SEQ ID NO: N-Suc-AAPI-pNA 8 SEQ ID NO: N-Suc-YVAD-pNA 70 SEQ ID NO: N-Suc-IEGR-pNA 18 SEQ ID NO: N-Suc-AAA-pNA 2 N-Suc-AAV-pNA 5 N-Suc-GGG-pNA 1 N-Suc-GGF-pNA 3 N-Suc-GGL-pNA 1 N-Suc-GFG-pNA 1 N-Suc-GPK-pNA 2 N-Suc-VGR-pNA 3 N-Suc-YLV-pNA 0 N-Suc-FVR-pNA 1 N-Suc-PFR-pNA 1 N-Suc-F-pNA 1 N-Suc-M-pNA 8 N-BZ-C-pNA 2 N-BZ-Y-pNA 20 N-BZ-R-pNA 1

[0145] Nicotianalisin Protease Substrate Specificity:

[0146] A comparison of the proteolytic activity of purified Nicotianalisin and in vivo proteolysis on hGH. To complement the results of the data in FIG. 1, purified Nicotianalisin protein was incubated with purified hGH protein in an in vitro assay, and analyzed by SDS-PAGE and Western blotting using hGH antibody. FIG. 7 shows a Coomassie stained gel of purified hGH cleaved by purified protease at 30° C. for 10, 20, or 30 min in the presence or absence of protease. Lane 1 contains protein molecular weight markers. Lanes 2, 3, and 4 represent hGH cleavage after 10, 20, and 30 min by Nicotianalisin respectively. The faint higher molecular weight bands may constitute Nicotianalisin. Controls for 10, 20 and 30 min incubations are shown in lanes 5, 6, and 7 respectively. Similarly, in FIG. 8 lane 1 contains pre-stained protein molecular weight markers. Lanes 2, 3, and 4 represent hGH cleavage by Nicotianalisin after 10, 20, and 30 min respectively. hGH after 30 min incubation at 37° C. in the absence of protease is shown in lane 5 as a control. Two prominent immunoreactive degradation products were detected (FIGS. 7 and 8) that are very similar in size to those observed after in vivo proteolysis in plants expressing hGH from a viral vector as shown in FIG. 1. The degradation products are also very similar in size to those reported in mammalian systems. A reduction in the amount of possible hGH dimmer is also observable in lane 5 compared to lanes 2, 3 and 4. Data from the in vitro cleavage studies and the characterization of the proteolytic activity of the Nicotianalisin protease clearly demonstrate that the protease identified from the IF is involved in the degradation of the hGH protein in vivo.

EXAMPLE 2

[0147] Cloning a Family of N. benthamiana Subtilisin-Like Protease cDNA Fragments.

[0148] RT-PCR amplification of Plant Subtilisin-Like Protease Catalytic Domains from N. benthamiana and Arabidopsis.

[0149] Several factors were considered when the PCR primers were designed to clone a fragment of the N. benthamiana subtilase gene. Biochemical characterization of the purified Nicotianalisin protein revealed high identity with a plant subtilisin-like serine protease. N-terminal sequence data supported that observation and indicated homology between Nicotianalisin and the tomato subtilase family. Plant subtilisin-like genes include a 15-member tomato gene family (Meichtry, Amrhein, and Schaller, 1999) and others (Batchelor et al., 2000; Jorda et al., 1999; Jorda, Conejero, and Vera, 2000; Neuteboom et al., 1999; Yamagata et al.,(2000) Berger, 2000 #6112). Based on the fact that all members of the subtilisin family contain a highly conserved catalytic domain (Siezen and Leunissen, 1997), primers were designed to the tomato catalytic triad and used to amplify an internal fragment of the N. benthamiana subtilisin-like serine protease gene. In addition, to test the hypothesis that this is a general method for cloning similar genes from other plants, the tomato primers were also used to amplify an internal fragment of a subtilisin-like protease from Arabidopsis thaliana.

[0150] Total RNA was prepared from whole plants by the hot borate RNA extraction method (Krieg, 1996). Nucleotide sequence from the tomato subtilisin-like protease (Tornero, Conejero, and Vera, 1996) was used to design PCR primers to amplify a conserved catalytic domain. The non-degenerate tomato primer 5′ GTG AGG GCA AGA CAT TGA TGT GCC TGA TAT GAT ATT GAA 3′ SEQ ID NO: 1, was used for first strand synthesis using the RETROscript™ RT-PCR kit (Ambion, Austin, Tex.). PCR amplification of the cDNA proceeded with the addition of the primer, 5′ GGC GTG ATT ATC GGA GTT ATA GAC 3′ SEQ ID NO:2, in a Perkin-Elmer 2400 GeneAmp PCR System for 35 cycles, each consisting of 94° C., for 20 sec, 40° C. for 30 sec and 72° C. for 40 sec.

[0151] The RT-PCR amplified N. benthamiana and A. thaliana DNA fragments were visualized in agarose gels by ethidium bromide staining and a single DNA band of approximately 1200 bases was observed for both PCR products (FIG. 9). The size of these fragments concur with the tomato (Tornero, Conejero, and Vera, 1996) and the Arabidopsis (Ribeiro et al., 1995) reported sequences for this region.

[0152] cDNA Cloning and Sequencing. Following amplification of the appropriately-sized bands (FIG. 9), fragments from both N. benthamiana and A. thaliana were cut from the gel and DNA cloned into the pCR® 2.1-TOPO® vector as per manufacturers instructions (Invitrogen, Carlsbad, Calif.). Sequencing of all cDNA clones was performed using the ABI 310 Genetic Analyzer (Applied Biosystems, Foster City, Calif.). The sequence was further analyzed using the Sequencher software program. The nucleotide and deduced amino acid sequences were analyzed using DNAMAN Sequence Analysis Software (Lynnon BioSoft).

[0153] The sequences of the N. benthamina and A. thaliana PCR fragments were homologous to the tomato (Tomero, Conejero, and Vera, 1996) and Arabidopsis (Ribeiro et al., 1995) subtilisin-like proteases. Sequence alignment of the N. benthamina gene fragments, NbP2-NbP7, revealed that they represent two contigs. NbP6 alone is one contig and the other five clones (NbP2, NbP3, NbP4, NbP5, and NbP7) form the second contig. Therefore, the NbP3 (SEQ ID NO: 3) and NbP6 (SEQ ID NO: 4) sequences were used to represent the two different genes.

[0154] The deduced amino acid sequences of SEQ ID NO: 3 and SEQ ID NO: 4 (i.e., SEQ ID NO: 24 and SEQ ID NO: 25, respectively) have characteristic motifs that are shared with other plant subtilisins. Three potential asparagine-linked glycosylation sites that are present in p69A and conserved in the tomato family (Meichtry, Amrhein, and Schaller, 1999), are also conserved in SEQ ID NO: 24 (FIG. 10). SEQ ID NO: 25 has two of the conserved N-glycosylation sites (FIG. 10). The Asp-His-Ser catalytic triad that is conserved in other subtilisins, including the tomato family (Meichtry, Amrhein, and Schaller, 1999), is also conserved in N. benthamiana (FIG. 10). In addition, SEQ ID NO: 24 and 25 both contain the highly conserved and catalytically important Asn residue that is known to stabilize the tetrahedral transition state of the enzyme reaction of subtilisin-like proteases (Gensberg, Jan, and Matthews, 1998; Siezen and Leunissen, 1997).

[0155] The tomato non-degenerate primers used in this study amplified both the N. benthamiana and the A. thaliana subtilisin-like gene fragments. Sequence analysis revealed 83% deduced amino acid residue identity between the tomato p69A subtilase gene fragment (Tomero, Conejero, and Vera, 1996) and the N. benthamiana subtilisin-like serine protease gene fragments. In the case of the Arabidopsis gene fragment, SEQ ID NO: 1 primer sequence was approximately 90% identical to the reported Arabidopsis sequence (Ribeiro et al., 1995). The deduced amino acid sequence covering this primer region is also highly conserved in all plant subtilisin-like proteases (FIG. 11). The conservation of the sequence may allow this method to be used to clone subtilisin-like proteases that have not yet been identified from other organisms.

EXAMPLE 3

[0156] Down-Regulation of Endogenous N. benthamiana Subtilisin-like Serine Protease Activity Using a Plant Viral.

[0157] Antisense and sense expression of a N. benthamiana subtilisin-like gene fragment in a TMV-based viral vector. Viral vectors have been shown to induce gene silencing in plants (Baulcombe, 1999; Lindbo, Fitzmaurice, and della-Cioppa, 2001). In addition, plant metabolic pathways have been altered via the delivery of viral-vector mediated gene silencing (Kumagai et al., 1995). To inhibit the endogenous proteolytic activity of Nicotianalisin in vivo, SEQ ID NO: 3, a partial cDNA sequence of the N. benthamiana subtilisin-like protease, was placed under control of the TMV-U1 coat protein subgenomic promoter in both the sense and antisense orientation (FIGS. 12A and B). Unique Pst I/Not I and No I/Pst I restriction sites were added at the 5′ and 3′ ends, respectively, of the SEQ ID NO: 3 gene fragment using PCR mutagenesis. The fragments were subcloned into TMV expression vectors in the antisense and sense orientation using methods that have been previously described (Kumagai et al., 1995), generating the TMV silencing vectors, pLSB2200 and pLSB2201 (FIGS. 12A and 12B). In addition, green fluorescent protein (GFP) was cloned into a TMV expression vector in the sense orientation and used as a control vector. Infectious RNA was generated using an mMESSAGE mMACHINE™ capped RNA transcription kit (Ambion, Austin, Tex.) as per manufacturer's recommendations and used to inoculate N. benthamiana plants as previously described (Kumagai, et al., 1995; McCormick et al., 1999). At 10 days post-inoculation leaves were harvested, and the plant IF fraction was isolated. Aliquots of the plant IF extracts were assayed for inhibition of protease activity using the synthetic substrate, N-Suc-Ala-Ala-Pro-Leu-p-NA SEQ ID NO:, and substrate-imbedded Zymogram gels as described in Example 1. The protease activities of IF extracted from GFP-inoculated plants and non-inoculated plants were used as controls.

[0158] Plant viral vector, pLSB2200 (FIG. 12A), expressing the N. benthamiana subtilisin-like protease gene fragment in the antisense orientation, mediated the down regulation of Nicotianalisin protease activity in N. benthamiana leaves. FIG. 13, shows a significant reduction of protease activity in the IF from an infected plant (lane 3) compared to the activity in IF from an uninoculated plant (lane 1) or a control plant infected with a viral vector expressing GFP (lane 2) as assessed by the in situ protease gel assay (see assay description in Example 1).

[0159] The inhibition of protease activity was also observed in plants inoculated with the sense construct, pLSB2201 (FIG. 12B). As summarized in Table 4, a similar reduction of protease activity was observed in plants inoculated with either sense or antisense infectious RNA as compared to uninoculated or GFP vector control plants.

[0160] Table 4. Percent reduction protease activity. IF was prepared from virally-infected and uninoculated plant leaves. Proteolytic activity was monitored by the hydrolysis of the synthetic substrate, N-Suc-AAPL-p-NA SEQ ID NO: as described in Example 1. Reduction of the protease activity was reported as the relative activity as compared to the activity in the IF from an uninfected plant (control). Plant Vector Relative Activity Uninoculated 100% GFP vector control 100% pLSB2201 (sense)  40% pLSB2200 (antisense)  30%

[0161] This result is similar to a previous study that demonstrated a manipulation of the carotenoid biosynthetic pathway in plants using plant viral vectors expressing gene and gene fragments in both the sense and antisense orientation (Kumagai et al., 1995).

EXAMPLE 4

[0162] Down-Regulation of N. benthamiana Subtilisin-Like Serine Protease Activity Using TRV and TMV Plant Viral Vectors.

[0163] Tobacco rattle virus (TRV) has also been shown to mediate gene silencing in plants (Ratcliff, Martin-Hernandez, and Baulcombe, 2001; Ratcliff, MacFarlane, and Baulcombe, 1999). The upper leaves emerging after infection show little to no viral symptoms, but still exhibit post-transcriptional gene silencing of nuclear genes (Ratcliff, MacFarlane, and Baulcombe, 1999). In addition, it has been shown that these upper leaves can be re-inoculated with another, distinctively different plant viral vector that can express a heterologous protein. Therefore, a strategy was developed utilizing both TRV and TMV to silence endogenous Nicotianalisin protease activity and express recombinant human growth hormone protein in planta.

[0164] Construction of TR V-SEQ ID NO: 3 sense and antisense. Tobacco rattle virus (TRV) RNA-2 encodes a capsid protein and two non-structural proteins, 2b and 2c. RNA-2 is not essential for infection in plants. It has been previously modified for expression of heterologous proteins. In this example, construct TRV-GFP (MacFarlane and Popovich, 2000), which has the 2b and 2c genes of TRV RNA-2 replaced with the pea early browning virus (PEBV) coat protein subgenomic promoter, was modified by PCR-directed mutagenesis. Oligonucleotides (5′-GTCCTAATCCCTAGGGATTTAAGG-3′ SEQ ID NO: 32, upstream, TRV2AVR2) and (5′-CTTTGGAAATTGCAGAAAC-3′ SEQ ID NO: 33, downstream, TRV4307-4289) were used to PCR amplify the region between the Avr II and Pst I sites of plasmid TRV-2b-GFP (MacFarlane and Popovich, 2000), which is similar to TRV-GFP except that it retains the 2b gene. Oligonucleotides (5′-GTTTCTGCAATTTCCAAAG-3′ SEQ ID NO: 34, upstream, TRV4289-4307) and (5′-GAATTCGGGGTACCGCGGCCGCGATATCCTGCAGGGCGTTAACTC-3′ SEQ ID NO: 35, downstream, TRVPST/NOT PL) were used to PCR amplify the region between the Pst I site and the 3′-end of the PEBV coat protein subgenomic promoter of construct TRV-2b-GFP. The two resulting PCR fragments were then joined by splice overlap PCR using oligonucleotides TRV2AVR2 and TRVPST/NOT PL and cloned into TRV-GFP digested with Avr II and Kpn I. The resulting construct, pK20-2b-P/N-SmaI, includes the 2b gene and has unique Pst I, EcoRV, and Not I cloning sites, with a Sma I site at the 3′-terminus of the TRV RNA-2 cDNA insert. Construct pK20-2b-N/P-SmaI, in which the Pst I and Not I sites were reversed, was constructed as described above, except oligonucleotide (TRVNOT/PST PL, 5′-GAATTCGGTACCCTGCAGGATATCGCGGCCGCGGCGTTAACTCGG-3′ SEQ ID NO: 36) was used instead of oligonucleotide (TRVPST/NOT PL SEQ ID NO: 35).

[0165] The subtilisin-like protease cDNA from N. benthamiana containing unique Nsi I and Not I sites at the 5′ and 3′ ends, respectively, was PCR amplified from plasmids pLSB2201 (sense orientation) and pLSB2200 (antisense orientation) using the following oligonucleotides (5′-TGGTTCTGCAGTTATGCATAGGCGTGATTATCGGAGTTATAG-3′ SEQ ID NO: 37, upstream) and (5′-TTTCCTTTTGCGGCCGCGTGAGGGCAAGACATTGATG-3′ SEQ ID NO: 38, downstream). The subtilisin protease gene fragment was then subcloned into the Pst I/Not I sites of pK20-2b-P/N-SmaI in the sense orientation and the Not I/Pst I sites of pK20-2b-N/P-SmaI in the antisense orientation. The resultant TRV RNA2-SEQ ID NO: 3 sense and antisense constructs were pLSB2223 and pLSB2224, respectively (FIG. 14).

[0166] Accumulation of hGH in a dual-virus expression system. TRV RNA2-SEQ ID NO: 3 sense construct pLSB2223 (FIG. 14), was linearized with Sma I and transcribed using T7 RNA polymerase (Ambion mMessage mMachine). N. benthamiana plants were inoculated with a mixture of transcript of RNA2 with transcripts from a full-length clone of TRV RNA-1. Transgenic plants expressing GFP were also used as a control to monitor gene silencing using a vector carrying gfp in RNA-2.

[0167] At 9 days post-inoculation the GFP expression in the GFP transgenic plants that were inoculated with TRV-2b-GFP RNA2 was silenced. Therefore, TRV RNA2-SEQ ID NO: 3-infected plants were then inoculated with a TMV-expression vector containing the hGH gene as described in Example 1. Eight to 10 days post TMV inoculation, plants were analyzed for hGH accumulation by Western immunoblot. The effect of in vivo reduction of Nicotianalisin activity by the recombinant TRV on the accumulation of a recombinant protein (hGH) expressed by a TMV vector is represented in FIG. 15. In the pLSB2223 TRV RNA2 SEQ ID NO: 3 infected plants, intact hGH accumulation (Lane 3, FIG. 15), was significantly higher than in plants not previously infected with TRV RNA2 SEQ ID NO: 3 (Lane 2, FIG. 15) suggesting that endogenous Nicotianalisin protease activity was down regulated.

EXAMPLE 5

[0168]N. benthamiana Subtilisin Gene Family and Strategies to Suppress the Protease Activity.

[0169] Isolation and characterization of N. benthamiana cDNAs homologous to the subtilisin-like protease. Several N. benthamiana cDNA libraries were constructed using whole plant, roots, apical meristem, and flowers of N. benthamiana. Individual clones were picked randomly, partially sequenced (resulting in an expressed sequence tag; EST), annotated and the information deposited in a searchable database. Several cDNAs, in addition to SEQ ID NO: 3 and SEQ ID NO: 4, with homology to other subtilisin-like proteases were found following querying of the database. These thirteen additional cDNAs are shown in Table 6 with their corresponding clone names: 28965 (SEQ ID NO: 5). 48994 (SEQ ID NO: 6), 103775 (SEQ ID NO: 7), 103965 (SEQ ID NO: 8), 108459 (SEQ ID NO: 9), 111767 (SEQ ID NO: 10), 113167 (SEQ ID NO: 11), 114340 (SEQ ID NO: 12), 155186 (SEQ ID NO: 13), 266847 (SEQ ID NO: 14), 272011 (SEQ ID NO: 15), 272344 (SEQ ID NO: 16), and 274641 (SEQ ID NO: 17). With the exception of SEQ ID NO: 12, both partial and full open reading frames (ORF) of SEQ ID NO: 3 to 17 were generated based on the homology to the Genbank sequences. SEQ ID NO: 12 produced several disrupted ORFs that may indicate that it is a pseudogene. However, additional data are needed in order to determine the role of this ORF. These fourteen Nicotianlisins (SEQ ID NO: 18-29, and 39-40) were aligned against fourteen homologous subtilisin-like proteases, and the results are shown in FIG. 11. The two peptide sequences derived from the purified protease fraction isolated from the plant IF (FIG. 11, SEQ ID NO: 30 and SEQ ID NO: 31) were found to match the deduced amino acid sequences of two different cDNAs: SEQ ID NO: 7 and SEQ ID NO: 17. As the deduced amino acid sequence of SEQ ID NO: 7 (i.e., SEQ ID NO: 19) lacks the N-terminal portion that would be examined for identity with the peptide sequence SEQ ID NO: 30, the possibility cannot be excluded that both SEQ ID NO: 30 and SEQ ID NO: 31 might be found in a deduced amino acid sequence of a full-length version of the gene represented by SEQ ID NO: 7. However, the deduced amino acid sequence of SEQ ID NO: 17 (i.e., SEQ ID NO: 18) contains the genetic regions correlating with both peptides, but was only identical with SEQ ID NO: 30, and not with SEQ ID NO: 31. This indicates that the IF of N. benthamiana leaves accumulates proteases expressed from at least one, and more likely two genes.

[0170] The gene represented by SEQ ID NO: 17 contained a partial open reading frame (ORF) of 2196 base pairs, coding for a polypeptide of minimum 737 amino acids and a deduced processed polypeptide of 620 amino acid with predicted molecular mass of 66,915 Da.

[0171] All fifteen sequences were aligned using the DNAMAN sequence analysis program, and the alignment and the deduced phylogenetic tree, are shown in FIGS. 10A and 10B. Based on this alignment, different variable and conserved regions of the sequences (FIG. 16A) were chosen as targets for making RNAi constructs to reduce the protease expression in plants (Table 6). There are two blocks of conserved sequence (Regions A and B) found in the alignment (FIG. 16A). Genes that share≧74% homology were grouped into single clusters. This resulted in eight different clusters representing 15 genes (Table 6). The variable regions represent a sequence that is unique to an individual gene. The conserved regions represent similar regions among closely related genes and, therefore, this sequence may be used to target genes in the same cluster for silencing.

[0172] In addition, the MALDI-TOF mass spectrum (see Example 1) concludes that the protein appears to be glycosylated. The mass data indicates that Nicotianalisins are 15% glycosylated. Percent glycosylation was calculated based on the mass difference between the theoretical and measured mass of isolated Nicotianalisin as determined by MALDI-TOF. The size of the mature protease and the presence of theoretical glycosylation sites in the deduced amino acid sequence concur with other plant subtilisin-like proteases that have been reported.

EXAMPLE 6

[0173] Reduction of Plants' Subtilisin-Like Protease Activities by Expression of Sense and Antisense of Subtilisin Genes.

[0174] Viral induced gene silencing approaches. Foreign proteins expressed in N. benthamiana via viral vectors are sometimes degraded by plant proteases. We found that the IF from the leaf possesses at least two subtilisin-like peptides that are associated with protease activities. These peptide sequences were present in clones SEQ ID NO: 7 and SEQ ID NO: 17. In order to facilitate the accumulation of foreign proteins in plants, plants are inoculated with a TRV vector containing a piece of a subtilisin-like gene. Since TRV is a strong silencing vector, this initiates the silencing of endogenous subtilisin gene(s). Then, these plants are inoculated further with a TMV vector containing the desired protein gene. One can attempt to selectively silence each individual gene using a unique sequence in the variable region, or one can concatenate two or more units to silence more genes. In addition, one can silence related genes using the conserved unit for each cluster. Again, one can concatenate these conserved units to silence several groups or all of the subtilisin genes. One can selectively use a combination of variable and/or conserved units to obtain a desirable trait (accumulation of protein) while limiting possible undesirable effects of reduced expression of one or more protease genes on the plant's growth.

[0175] Transgenic plant approaches. The gene silencing strategy can also be used in stably transformed plants (e.g., via Agrobacterium-mediated transformation, transposons and other genome integrating vectors) expressing these variable and conserved units. However, this type of silencing in plants is generally less effective than the transient (viral vector-mediated) method described above. Recently, expression of double-stranded RNA (ds-RNA) was found to significantly increase the efficiency and degree of silencing in stably transformed plants (Chuang and Meyerowitz, 2000; Waterhouse, Graham, and Wang, 1998). This construction typically has the sense and antisense units interrupted by a loop. This loop can be a fragment of coding region or an intron, and it is expected to form a hairpin structure following transcription. One can adapt this ds-RNA method as a more efficient way of silencing the proteases in plants. In this case, transgenic plants containing the silencing unit are inoculated with a TMV vector expressing the protein of interest. Two weeks post-inoculation, the accumulated protein is purified from leaves. Similarly to the transient method above, one can combine the effects of different units by concatenating these units into a single construct. Another way to combine these units is to sexually cross transgenic plants carrying individual or multiple units, and then screen the progeny for the presence of both transgenes. The expression of the silencing unit can be driven by any largely constitutive promoter such as those derived from CaMV 35S, actin, rubisco, or ubiquitin. However, silencing of certain unit(s) may cause aberrations or a lethal phenotype in transformed plants. To overcome problems caused by constitutive silencing of the protease(s), an inducible promoter is used to facilitate induction of silencing shortly before infection with the viral vector expressing the gene of interest, thus allowing the protein of interest to accumulate, but minimizing the time for undesirable phenotypes to develop. Promoters have been isolated that have been shown to be inducible in transgenic plants by glucocorticoid (Martinez et al., 1999), salicylic acid (Lebel et al., 1998), or copper (Mett, Lochhead, and Reynolds, 1993). In this case, the transcription of the silencing unit(s) is driven by any appropriate inducible promoter(s). Transformed plants are obtained in the absence of the inducer. In the case of targeting individual genes or subgroups, it is important to design the trigger dsRNA carefully to take into account the possibility of transitive RNAi (interfering RNA) causing unintended silencing of homologous genes (Nishikura, 2001).

[0176] Either the protein of interest, such as hGH and/or the genetic element capable of reducing protease activity maybe stably incorporated into the host genome by conventional techniques. Either direct protease inhibitors such as aprotinin or inhibitors to prevent formation of the protease may be used. When the genetic element and/or the protein of interest interfere with the functioning of the plant, either or both may be under regulatory control, which can be altered. For example, by using an inducible promoter, one can culture the transgenic plant without expression of the genetic element and/or the protein of interest. At a selected time, an inducer may be added or the conditions changed to allow the promoter to express the genetic element and/or the protein of interest. Likewise, the opposite may be done for repressors and indirect regulatory elements.

[0177] When using transgenic plants and only one of the gene for the protein of interest or the genetic element is present, the other may be added by using a vector. TABLE 6 N. benthamiana cDNA Clones Homologous to Subtilisin-Like Proteases Conceptual Relative a.a. N.A. translated coverage of Name of Name of Name of SEQ Clone protein, Homologous Protein and its homologous Variable Conserved Conserved ID Name SEQ ID Annotation Protein region region A region B 17 274641 18 Alnus glutinosa, S52769  ˜8-760   V1  C1A C1B subtilisin-like proteinase ag12 (761) 7 103775 19 Alnus glutinosa, S52769 150-430 V2  C2A C2B subtilisin-like proteinase ag12 (761) 11 113167 20 Alnus glutinosa, S52769  60-755 V3  C1A C2B subtilisin-like proteinase ag12 (761) 8 103965 21 A thaliana, BAB02339  7-770  V4**  C4A**  C5B** cucumisin-like serine protease (777) 5 28965 22 A thaliana, BAB02339  7-770 cucumisin-like serine protease (777) 16 272344 23 A thaliana, BAB02339  ˜6-769   V5  C4A C5B cucumisin-like serine protease (777) 3 NbP3 24 Tomato, T06580 subtilisin-like 140-540 C6A C8B proteinase p69f (747) 4 NbP6 25 Tomato, T06580 subtilisin-like 140-534 C6A C8B proteinase p69f (747) 14 266847 39 Tomato, T06580 subtilisin-like 139-388 V8* C6A C8B proteinase p69f (747) 15 272011 40 Tomato, T06580 subtilisin-like 139-388 C6A C8B proteinase p69f (747) 9 108459 26 Tomato, T07172 subtilisin-like 614-775 V10 proteinase (775) 10 111767 27 Tomato, T07171 subtilisin-like  1-766 V11 proteinase SBT1 (766) 12 114340 A thaliana, AAD12260 subtilisin- ˜150-522   V12 like protease (772) 13 155186 28 Tomato, CAA07250 serine 404-745 V13 protease (747) 6 48994 29 A thaliana, AAF76468 similar to 593-755 V14 p69d gene of tomato (756)

EXAMPLE 7

[0178] Reduction of Plants' Subtilisin-Like Protease Degradation of a Protein by Simultaneous Expression of a Protease Inhibitor Gene.

[0179] Human and porcine Stem Cell growth Factor (SCF) genes were cloned in GENEWARE® vectors either alone (neat) or fused to either a 6 histidine tag, an HDEL tag, both 6-His and HDEL or an aprotinin gene connected by a cleavable linker. The vector design for the fusion to aprotinin gene is shown in FIG. 17. Controls of a GENEWARE® vector containing gfp (clone 5), aprotinin cloned in a GENEWARE® vector, E. coli-produced recombinant hSCF purified protein and purified natural aprotinin were also prepared.

[0180] The vectors were used to inoculate plant leaves of different sets of plants as described in the examples above. Both plant homogenates and interstitial fluid were extracted as described above. hSCF and pSCF were each purified from 27 plants to yield 0.85 mg (˜15 mg/kg) and 2.5 mg (˜45 mg/kg) of protein respectively. Recovered proteins were biologically active in CD34+ proliferation assays

[0181] Samples from some of the experiments were taken and subjected to SDS-PAGE and stained with Coomassie Blue. The gel is shown as FIG. 18. Within the protein rich homogenate, little specific production can be seen but in the interstitial fluid (IF) fractions, it is possible to see a protein band in the location of SCF and aprotinin when using a vector expressing both genes. Such bands are not readily apparent in lanes where the vector lacked aprotinin.

[0182] To distinguish SCF proteins from other cellular proteins of little interest, a Western blot was performed using various samples and an antibody against hSCF that cross reacted with pSCF. The result is shown as FIG. 19. The first lane with recombinant hSCF produced by E. coli is unglycosylated and has a lower molecular weight than hSCF produced in plants. The HDEL tagged proteins were preferentially retained in the endoplasmic reticulum. Because the antibody was generated against human SCF, it reacts less with porcine SCF. Hence the pSCF should be in higher concentrations than it appears. Interstitial fluid samples show the proteins were mostly degraded.

[0183] The Western blot experiment was repeated focusing on comparing the regions for both SCFs and their degradation products. This time, interstitial fluid from plants infected with GENEWARE® vectors containing aprotinin-hSCF and aprotinin-pSCF were compared to hSCF and pSCF. The key region is shown in FIG. 20. The quantity of higher molecular weight SCF protein was higher and the quantity of lower molecular weight degradation products was reduced. This suggests the presence of aprotinin reduced proteolysis compared to the same expression system without expression of aprotinin.

[0184] Although the invention has been described with reference to the presently preferred embodiments, it should be understood that various modifications can be made without departing from the spirit of the invention. All publications, patents, patent applications, and web sites are herein incorporated by reference in their entirety to the same extent as if each individual patent, patent application, or web site was specifically and individually indicated to be incorporated by reference in its entirety.

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1 40 1 39 DNA Primer 1 gtgagggcaa gacattgatg tgcctgatat gatattgaa 39 2 24 DNA Primer 2 ggcgtgatta tcggagttat agac 24 3 1194 DNA Artificial Sequence TMV Vector Construct 3 ggcgtgatta tcggagttat agacactgga attttccctg accatccttc atttagcgac 60 gttgggatgt ctcccccgcc tgctaagtgg aaaggatttt gtgagtccaa tttcacgaca 120 aagtgtaata acaagatcat aggactcagg tcttttcgat tatctgaaga taccccgata 180 gatactgatg gacatggtac acacactgct agcacagctg caggagcttt tgtgaaaggt 240 gccaatttct ttggtaatgc aaatggcaca gcagttggtg ttgcccctct tgcccacatg 300 gccatatata aggtatgcag ttttgctact tgtagtgaaa ctgatgcttt agctgccatg 360 gatgcagcta tagatgatgg tgtagatatc atttccgcat ctctaggcgg atttactaac 420 gctccattac atgatgaccc tatttctctt ggcgcgtaca gtgcaacaga aaaaggtatt 480 ctngctagtg cctctgcagg caatagcgag tttgataacc ctgtagcaaa taatgcccct 540 tggattctca cagttggcgc tagcacccat gatagaaaac taaaagccac cgttaagctt 600 ggaaataaag aggaatttga aggagaatct gctgatcagc caaagacttc caactcaaca 660 ttcatcgctc tatttgatgc tggaaagaat gcaagtgatc aagatgctcc attctgtaga 720 tcgtgggcga tgactgatcc tgctatcaaa ggtaagatag tcttgtgtca aaaagaccca 780 agtagtctca ccagtagtca aggacgaaat gtaaaggacg ctggaggcgt tggcatgatt 840 ctcatcaata atccggaaga tggtgtcact aaatcagcta ctgctcatgt tcttcccgca 900 ttagatgttt cacatgaaga aggagagaaa attaaggcct atataaattc aacttcaaat 960 cctattgctg caattacatt ccagggaaca gtaataggag ataaaaatgc tcctattgtt 1020 gcttcatttt ctgctcgagg accaagccga gcaaaccctg gcatcttaaa acctgatatt 1080 attggtcctg gtgttaatat ccttgctgct tggcctacca ccgtgaatat ccccaacaaa 1140 aacacaaatt ctggattcaa tatcatatca ggcacatcaa tgtcttgccc tcac 1194 4 1194 DNA Artificial Sequence TMV Vector Construct 4 ggcgtgatta tcggagttat agacactgga attgttcctg accatccttc atttagcgac 60 gttgggatgc ctcctccgcc tgctaaatgg aaaggatttt gtgagtctaa tttcacgacc 120 aagcgtaaca acaaactcat tggagccagg tctttcccgc ttgacaatgg tcccatagat 180 gaaaatggac atggtacgca tacagcaagc acagctgcag gagcctttgt gaaaggtgct 240 aatgtatttg ggaatgccaa tggaacagca gttggtgttg cccctcttgc gcacatagcc 300 atatataagg tatgcggttc tgatggcgtt tgttctgatg ttgaaatttt acctgcgatg 360 gatgtagcta ttgatgatgg cgtagatatt ctatcaatat cccttggtgg aactagtaat 420 ccgttccata atgacaagat tgctcttggg gcgtatagtg caacagaaag aggtattctt 480 gttagttgtt ctgcaggcaa tagtggtcca ttccaacgca ctgtaaacaa tgacgcccct 540 tggattctca cagttggcgc tagcactcat gatagaaaac taaaggccac tgttaagctt 600 ggaaataaag aagaatttga aggagaatct gcttatcatc caaagacttc aagctcaaca 660 ttcttcactc tatttgatgt tgaaaaagat ggtacacgag caaccagagc ccctttctgc 720 ataccaggat cactcactga cccttctata aggggaaaga tagttgtgtg cctggttggt 780 ggtggcgttc gtacggttga taaaggacaa gttgtaaagg atgctggagg tgttggcatg 840 attcttatca ataatccaga agatggtgtt actaaatcag ctgaagctca tgtccttcca 900 gcattggatg tttcagatgc agatggaaag aaaattcttg cctacataaa ctcaacgtcg 960 aatcctgttg ctgcaatcac cttccatgga actgtacttg gagataaaaa tgctcctata 1020 gttgcttcat tttcttctcg aggaccaagc gaagcaagtc gtggcatctt gaaacctgat 1080 attattggtc ctggtgttaa tgtccttgct gcttggccta cctcagtaga taacaacaaa 1140 aacacaaaat ccacattcaa tatcatatca ggcacatcaa tgtcttgccc tcac 1194 5 2533 DNA Artificial Sequence Expresses homologous to A thaliana, BAB02339 cucumisin-like serine protease 5 cccacgcgtc cggtttttcc attctttttc attattatct ctttctgcct cactccggtg 60 accatttccg tccaatccga tggtcatgaa actttcatca ttcacgtttc caaatccgat 120 aagccccgtg ttttcaccac ccaccaccat tggtactcct ccatcatccg atccgtttcc 180 caacaccctt ctaaaatcct ctacacctat gaacgtgccg ccgtgggctt ctctgcacgc 240 ctcacagccg ctcaggccga tcagctccgc cgtattcccg gtgtaatctc cgtccttccc 300 gacgaagtac gccatctcca caccacccat acccctacct tcttgggact tgctgactct 360 ttcggccttt ggcccaactc cgattacgct gatgatgtca tcgtcggagt tctggacacg 420 ggtatatggc cggaaagacc gagtttttcc gacgagggtc tctctacggt tccttcaagt 480 tggaaaggga agtgcgttac tggacctgat tttcctgaaa cctcatgtaa taaaaaaatc 540 ataggcgctc aaatgtttta caaagggtat gaagctaaac atggcccaat ggatgaatca 600 aaagaatcaa aatcgccaag agatactgaa ggacatggaa cacatacagc atcaacagca 660 gctggttctt tagtggcaaa tgctagcttt taccaatatg ccaaaggtat ggctataaaa 720 gcaagaatag ccgcttacaa gatttgctgg aaaaatggct gttttaattc tgatatattg 780 gctgccatgg atcaagctgt tgatgatggt gtgcatgtga tctcactttc tgttggggct 840 aacggttatg ctccacatta tctgtatgat tctattgcaa ttggagcttt tggtgcatct 900 gaacatggcg tcctcgtctc atgttcagct ggaaattctg gtcccggagc ttatacggca 960 gtgaacattg ccccgtggat gctcactgtt ggtgcatcaa ctatagatcg tgagttcccg 1020 gcagatgtta ttttaggaga taatagaata tttggtggtg tttcattgta ctccggcaat 1080 cctttgaccg atgccaaatt gccggtggtt tattccggcg actgtggtag caaatactgt 1140 tatccaggaa agctagatcc taaaaaagtc gcaggaaaaa ttgttttatg cgatagggga 1200 ggcaacgcta gggttgaaaa agggagtgcg gtgaagcagg caggcggagt agggatgata 1260 cttgctaatt tggctgactc cggcgaagaa ctcgtcgccg attcacatct tctcccggcg 1320 acgatggtcg gtcaaaaagc tggagacaaa ataagacact acgtaacgtc tgatccttca 1380 cccacggcga cgatcgtgtt cagaggaaca gtgatcggaa aatcaccggc agcaccacgt 1440 gtagcggcgt tctcgagccg aggacctaat catttgacgc cggagattct taaaccggat 1500 gttattgcac ctggagttaa cattttggcc ggttggaccg gatctgttgg accgaccgat 1560 ttggatattg acacgagaag agtagaattc aatattattt ctggaacttc catgtcgtgc 1620 cctcacgttg ggggattggc tgctttactt agaagggccc acccaaagtg gaccccagca 1680 gcggtaaagt cagcacttat gacaacagct tacaacttgg acaattctgg taaagtattt 1740 acagatcttg ccactggcca agaatctact cccttcgttc atggatcagg tcatgtagac 1800 ccgaaccgag cattggatcc gggtttgatt tacgacatcg aaactagcga ttacgtaaat 1860 ttcctatgct ccatggctta tgacggcgac gatgtcgccg tgttcgcgag agattcttct 1920 cgagtgaatt gcagtgaacg aagtttggct actccgggag acctgaatta cccgtcgttc 1980 tccgttgttt ttaccggtga gagcaacggt gtggttaaat acaagcgggt ggtgaataat 2040 gtaggaaaaa atacagatgc tgtgtatgaa gtgaaggtga atgcgccgtc gtcggtggag 2100 gtgaatgtat caccggcgaa gcttgtattc agtgaggaaa agcaaagttt gtcgtatgag 2160 attagcttaa agagtaaaaa gagtggtgat ttgcagatgg tgaaggggat tgaatctgca 2220 tttgggtcga ttgaatggag tgatggaatt cacaatgtga gaagcccaat tgcggtgcgt 2280 tggcgtcact attctgatgc agcatccatg tgagtaatgg atgattgttc tttatattgc 2340 attgcatgga ccaataaact gggatgatga caaattgaaa gacgaaatgt tgctagagga 2400 tcatcgaatt tgtccaactt taatttcact ttctttacct tttgttctct gatgttgttc 2460 agattgatgt atatatgaat gaagcatacc cagttgtttc ccagaaaaaa aaaaaaaaaa 2520 aaaaaaaaaa aaa 2533 6 813 DNA Artificial Sequence Clone that expresses homologous to A thaliana, AAF76468 similar to p69d gene of tomato 6 ggccattacg gccgggcacg tgaatcctga atcggctatt gatccgggcc taatatacga 60 cactgataca tcagactaca tcaacctact atgcagcttg aactacacag agaaagaaat 120 gaaacttttc acgaacgagt caaatccttg ctcgggtttt actggatctc cacttgatct 180 taactatcca tcactttctg ttatgttcag gcctgattcc tctgttcatg ttgttaagag 240 gacattaaca catgtcgcgg tttctaagcc tgaggtgtac aaagtaaaga tactgaatct 300 gaattctgaa aaggttagtt taagtataag cccaatggag ctgatgttca atgaatcttt 360 aaggaaacaa aggtatatgg tcaaatttga gagccatcat atattcaaca gcagcaggaa 420 aatagctgag caaatggcgt ttggttcgat atcttgggag agtgaaaagc acaatgttag 480 gagccccttt gctgttatgt gggttcagca aaatttcaat aacagtagat tatacaaaat 540 aacttaatat gtacattgtt gtatctgttg tatcgtcgta cctctagcct ccgagtatgt 600 actatgttgt attacgtacc tctagcctct gagtatgtac tatgttgtat catcgtacct 660 ctagcctccg agtatgtact acgttgtatt acgtacctct agcctctgag tatgtactat 720 gttgtatcaa cgtacctcta gcctccgagt atgtagtatg tatatcattg tatctttagg 780 cctcaaaaaa aaaaaaaaaa aaaaaaaaaa aaa 813 7 869 DNA Artificial Sequence Expresses homologous to Alnus glutinosa, S52769 subtilisin-like proteinase ag12 7 tggtatcaac gcagagtgcc attacggccg gggatgatgg gattagtgaa gtaccatcaa 60 gatggaaagg agaatgtgaa agtggtactg agttcaattc ctctttgtgt aacaagaagc 120 tcattggcgc tcgttacttc aataaaggcc tacttgccaa caatccaaat cttaatattt 180 caatgaattc ttctagagat accgatggac atggaactca cacttcttct acagctgcgg 240 gaagttatgt tgagggtgca tcttattttg gctatgccac cggtactgct attggcatag 300 cgccaaaggc tcatgtggct atgtacaagg ctctatggga agaaggtgta tacttgtctg 360 atgttcttgc tgcaattgat caagcaatta cagatggtgt ggatgtctta tccttgtcgt 420 taggcataga cgcgattcca ctacacgaag atcctgtggc aattgccgca tttgctgcat 480 tggagaaagg tatatttgtt tccacctctg caggaaatga agggccttat tatgagactt 540 tgcacaatgg aacaccttgg gtgttaactg ttgcagctgg cacagttgac cgcgaattta 600 ttggaacatt aactcttgga aatggagttt cagtccctgg tttatcgcta taccctggga 660 attctagttc aagcgaaagc tcccttgtct atgtcgaatg ccaagatgac aaggaactgc 720 agaaaaatgc acacaaattt gttgtctgtc tcgacaagaa tgattcggtt ggtgagcatg 780 tgtacaatgt aagaaattca aaagttgctg gggctgtctt tataactaat acaactgact 840 tggaattcta cctccaaagc gaattcccg 869 8 2532 DNA Artificial Sequence Expresses homologous to A thaliana, BAB02339 cucumisin-like serine protease 8 gtttttccat tctttttcat tattatctct ttctgcctca ctccggtgac catttccgtc 60 caatccgatg gtcatgaaac tttcatcatt cacgtttcca aatccgataa gccccgtgtt 120 ttcaccaccc accaccattg gtactcctcc atcatccgat ccgtttccca acacccttct 180 aaaatcctct acacctatga acgtgccgcc gtgggcttct ctgcacgcct cacagccgct 240 caggccgatc agctccgccg tattcccggt gtaatctccg tccttcccga cgaagtacgc 300 catctccaca ccacccatac ccctaccttc ttgggacttg ctgactcttt cggcctttgg 360 cccaactccg attacgctga tgatgtcatc gtcggagttc tggacacggg tatatggccg 420 gaaagaccga gtttttccga cgagggtctc tctacggttc cttcaagttg gaaagggaag 480 tgcgttactg gacctgattt tcctgaaacc tcatgtaata aaaaaatcat aggcgctcaa 540 atgttttaca aagggtatga agctaaacat ggcccaatgg atgaatcaaa agaatcaaaa 600 tcgccaagag atactgaagg acatggaaca matacagcat caacagcagc tggttcttta 660 gtggcaaatg ctagctttta ccaatatgcc aaaggtgaag ctagaggtat ggctataaaa 720 gcaagaatag ccgcttacaa gatttgctgg aaaaatggct gttttaattc tgatatattg 780 gctgccatgg atcaagctgt tgatgatggt gtgcatgtga tctcactttc tgttggggct 840 aacggttatg ctccacatta tctgtatgat tctattgcaa ttggagcttt tggtgcatct 900 gaacatggcg tcctcgtctc atgttcagct ggaaattctg gtcccggagc ttatacggca 960 gtgaacattg ccccgtggat gctcactgtt ggtgcatcaa ctatagatcg tgagttcccg 1020 gcagatgtta ttttaggaga taatagaata tttggtggtg tttcattgta ctccggcaat 1080 cctttgaccg atgccaaatt gccggtggtt tattccggcg actgtggtag caaatactgt 1140 tatccaggaa agctagatcc taaaaaagtc gcaggaaaaa ttgttttatg cgatagggga 1200 ggcaacgcta gggttgaaaa agggagtgcg gtgaagcagg caggcggagt agggatgata 1260 cttgctaatt tggctgactc cggcgaagaa ctcgtcgccg attcacatct tctcccggcg 1320 acgatggtcg gtcaaaaagc tggagacaaa ataagacact acgtaacgtc tgatccttca 1380 cccacggcga cgatcgtgtt cagaggaaca gtgatcggaa aatcaccggc agcaccacgt 1440 gtagcggcgt tctcgagccg aggacctaat catttgacgc cggagattct taaaccggat 1500 gttattgcac ctggagttaa cattttggcc ggttggaccg gatctgttgg accgaccgat 1560 ttggatattg acacgagaag agtagaattc aatattattt ctggaacttc catgtcgtgc 1620 cctcacgttg ggggattggc tgctttactt agaagggccc acccaaagtg gaccccagca 1680 gcggtaaagt cagcacttat gacaacagct tacaacttgg acaattctgg taaagtattt 1740 acagatcttg ccactggcca agaatctact cccttcgttc atggatcagg tcatgtagac 1800 ccgaaccgag cattggatcc gggtttgatt tacgacatcg aaactagcga ttacgtaaat 1860 ttcctatgct ccattggcta tgacggcgac gatgtcgccg tgttcgcgag agattcttct 1920 cgagtgaatt gcagtgaacg aagtttggct actccgggag acctgaatta cccgtcgttc 1980 tccgttgttt ttaccggtga gagcaacggt gtggttaaat acaagcgggt ggtgaataat 2040 gtaggaaaaa atacagatgc tgtgtatgaa gtgaaggtga atgcgccgtc gtcggtggag 2100 gtgaatgtat caccggcgaa gcttgtattc agtgaggaaa agcaaagttt gtcgtatgag 2160 attagcttaa agagtaaaaa gagtggtgat ttgcagatgg tgaaggggat tgaatctgca 2220 tttgggtcga ttgaatggag tgatggaatt cacaatgtga gaagcccaat tgcggtgcgt 2280 tggcgtcact attctgatgc agcatccatg tgagtaatgg atgattgttc tttatattgc 2340 attgcatgga ccaataaact gggatgatga caaattgaaa gacgaaatgt tgctagagga 2400 tcatcgaatt tgtccaactt taatttcact ttctttacct tttgttctct gatgttgttc 2460 agattgatgt atatatgaat gaagcatacc cagttgtttc acagaaaaaa aaaaaaaaaa 2520 aaaaaaaaaa aa 2532 9 716 DNA Artificial Sequence Expression homologous to Tomato, T07172 subtilisin-like proteinase 9 cccacgcgtc cgatggtgca ggacacataa atccacgaaa agctgttgac cctggtttgg 60 tttatgacat aggggcgcag gattacttcg aattcctatg cacacaacaa ctcagccctt 120 cacagctaac agtttttgga aagttctcca acagaacttg ccatcactcg cttgctaatc 180 caggggactt gaactacccc gccatttctg cagtttttcc tgaagacgca aaagtttcaa 240 cgctgacgct tcacagaaca gtcaccaatg tgggttctcc aatatcaaat taccatgtta 300 gagtctcgcc gttcaaaggt gcagtcgtga aggttgagcc atcaagattg aatttcacca 360 gcaaacacca gaaactatct tacaaggtga ttttcgagac aaaatatcgt caaaaagcac 420 gtgaatttgg atccctgctt tggaaagatg ggacacacaa agtgagaagc acaattgtga 480 tcacatggct agcatcaatt tagttcagct tgccatttag taactagcat tttgtttgct 540 gaggataata aaaaacatgt tgcggcaaag tccctgtgtt ttcagcagtt gttttcagta 600 gaaaatagtt tcttttgttc attactagct acttatattg ccaaattatt tgtggcagct 660 actaaaatga tgaatttggc aataggagcc aaaaaaaaaa aaaaagggcg gccgcg 716 10 2691 DNA Artificial Sequence Expression homologous to Tomato, T07171 subtilisin-like proteinase SBT1 10 gctagcaccc aaccccctct ctaccaaagg aaagaaactc ttccctttca gtagagaact 60 tccattttct ggttacctga cactgagaac cgcaaaaaga tggcaagacc cgggggcatg 120 gttctttcaa cactattcct aatgttgttt catgtgtttg ttcatgcagg ccagaaccag 180 aaaaagactt acataattta catggacaag tccaacatac ctgctgattt tgatgatcac 240 actctgtggt atgactcatc tttaaagtca gtatccaaag gcgccaacat gctttacacc 300 tacaacaatg tcatccatgg ctactcaaca cagctaacag ctgatgaagc caaatctctt 360 gaacagcaac ctggaattct ctcggtccat gaggaagtga gatacgagct tcataccact 420 cgatccccta catttctggg acttgaagga cgtgaaagta aatcattctt tcttcaagct 480 gaaacaagga gtgaggtcat tattggtgtg ctggacactg gtgtttggcc tgaatcaaaa 540 agttttgatg acactggact aggtccagtc cctatgagct ggaagggtga gtgccaaatt 600 ggcaagaact tcaaagcatc aagctgtaac cggaaactca ttggtgcaag gtttttctca 660 caaggttatg aagcagcttt cggggcaatt gatgagacca cagaatccaa gtcaccaagg 720 gacgatgatg gccatgggac acacactgca actacagcag ctggctcggt tgtaacggga 780 gctagcctct ttggttatgc tgctggcaca gcacgtggga tggcttcaca tgcaagagtg 840 gctgcatata aagtatgttg ggctggagga tgttttagca gcgacatact agcagggatg 900 gatcaggccg tcatagatgg tgtaaatgta ctctcactgt cccttggtgg cacaatttct 960 gattattaca gggatatagt agcaattgga ggattttctg cagcttctca aggaatcttc 1020 gtctcgtgct cggctgggaa tggcgggcca ggctctggat ccctctccaa cgctgcacca 1080 tggataacta ctgtaggtgc ggggaccatg gaccgcgaat tcccagcata tattagcctt 1140 ggaaatggaa aaaaattcag tggagtatca ctttacagtg gaaaagcatt acctagttct 1200 gtgatgccac tggtgtatgc tggaaatgcc agccaagcat caaatggcaa tttatgcaca 1260 agtggtagtc tgattccaga aaaagttgat gggaaaattg tagtatgtga cagagggatg 1320 aatgcaaggg cacagaaggg tttggttgtc aaagatgctg gtggaatagg gatgattttg 1380 gcaaacacag actcttacgg agatgagttg gttgctgatg cmcatctcat accaacaggt 1440 gcagttggtc aaactgctgg tganttgatc naaaggtaca ttgcttctga cagtaatcca 1500 attaccacaa ttgcatttgg aggtaccaag ttgggcgtcc aaccatcacc ggtcgtcgca 1560 gcttttagtt ccagagggcc aaacccaatc acaccggaga tccttaaacc agatttgata 1620 gcaccaggtg tcaatattct tgctggctgg acaggaaaag ttggaccaac aggtttgcca 1680 gaagacacca ggaatgtggg tttcaacatc atctctggaa cttccatgtc atgtcnccat 1740 gtaagtgggc ttgcagcant actgnaagcc gcccatccag aatggagttn aggggtnata 1800 aggtcagcac tgatgactac aggttacagc acacacaaga atggnnaaat gatagaggat 1860 gttgccacag gaatgtcata tacaccagtt gatcatggcg ctggacatgt gaatccagca 1920 gcagctatga atcctgggtt agkgtatgat ctcacagttg atgactatat aaacttcctt 1980 tgcgccctgg attacagtcc aagtatgatc aaggtcatcg caaagcgaga tatttcctgc 2040 gnaaacaata aggatataga gttgctgacc ttaattaccc atcttttgcc attcctttgg 2100 aaacgggcct ggggcgaaca tgcaaatagt agtgcaccaa cagtgaccag atatacgagg 2160 actctaacaa acgtgggaaa tccagctaca tacaaggcct cagtctcttc tgaaatgcag 2220 gaagtgaaga ttcaggttga accacaaaca cttactttca gtcgaaagaa ggaaaagaaa 2280 acctacactg tgacattcac tgctagttcc aagccatcag gcacaactag ctttgctcga 2340 ctggaatggt cagatggaca acatgttgtt gctagcccaa ttgctttcag ttggacatga 2400 ttatgctaat tctataagtc attcactgca aatgtacaag tgcaaatatt cctataaaat 2460 aattactagt gtgcagcagc tactcctcta atattccacc aactaaaaaa atagccctga 2520 cctataatta agatgcctag gaaattctag catctagaca aggaaaatgt tggttgattt 2580 gtccagcaaa agacaggtgt tttacttgcc agattattat gtaccaagcc acacaatatg 2640 gataaataca attggctttc gaaaaaaaaa aaaaaaaaaa aaaaaaaaaa a 2691 11 2188 DNA Artificial Sequence Expression homologous to Alnus glutinosa, S52769 subtilisin-like proteinase ag12 11 acccctcgac cmacgcgycs gcccacgcgt ccgcccacgc gtccgctttc tccttccgag 60 tacaaagcca tcaagaattc tctagggtat gtttcttcga tggaggacag gacagttaaa 120 attcacacga cccattcatc ccatttcctt ggcctaagct caatgtatgg ttcatggcca 180 aagtcaaact atggcaaagg tgttatcatt ggtgtagttg atacaggggt ttggccagag 240 attaaaagct ttgatgatga tgggatgagc caagttccat caaggtggaa aggaatatgt 300 caaactggca ctcagtttaa ttcttcattg tgcaacaaga aactcatcgg agctcgttac 360 ttcaataaag gactactttc taaagtgaaa aatcttacca tcatgataaa ttctgcccgt 420 gatacagagg gacatggaac tcatacttcc tctacagctg ctggaagtct tgtaaagggt 480 gcgtcttatt ttggctatgc ccctggtttt gcaataggcg tcgcaccaat ggctcatgtg 540 gctgtgtaca aggctctctg ggatggggcc ggtaccattt ctgatattct tgctgcattg 600 gatcaggcaa ttgcggatgg ttgtgatatc ttatccttgt catttggcgc agtttctcca 660 ttccctctat atatagatcc tatctctatt gcttcatttt ctgcaatgga gaaaggcata 720 tttgtttccg tttcagctgg aaatgaaggg cctttcgatc aatctttgag caatgaggca 780 ccttggtttc tctctgttgc tgctagcaca gttgatcggg acgttatcag gatattaact 840 cttggtaatg gagtttcagt cactggttta tctctctacc ctgggaattc tacaagcgat 900 atttctgtta ttcttgtcaa gaattgctta gataagcagg aattgcaaaa tgttacagac 960 aaatttgtgg tctgcattga caaaaacgca ttggtcggga aacaagttga aagtgtgaga 1020 cattcaaatg ctgctggtgc tgtcttcata acaaatgact ttgtcactga cttgggcgaa 1080 tacctcaaaa cagaattccc atctgtgttt ctgaatttcc aaaatggtga tcaagttttg 1140 aaatatgtta acagcacttc ttcaccaaaa gcaaagattg gacttcaagg gacactaatt 1200 ggtgtcgaac gagcaccagc tgtcgcgcat tttagttcga gggggccatc aatgacctgc 1260 ccgtttatcc tcaaacctga cctgatggct ccaggtcact taatactagc ttcatggtct 1320 ccactatcat ctgtgagtcc atatactgaa cttcacaata tctttaacat tatatctggc 1380 acatccatgt catgtccaca cgctgccggt gtagctgcac ttgttaaagg gacccaccct 1440 gaatggagcc cagctgccat tcgttcggcc atgatgacta cagcggatgt tctagacaac 1500 acacaaagtc cgatccaaga catcggtcgt ccagagaatg ctgctgctac tcctcttgct 1560 atgggagctg gccatatcaa tcctaacaag gcaatagatc ctggactcat ctatgataca 1620 acaccacaag attacattaa tcttctttgt gctctaaatc tcacatccga gcagataaaa 1680 accatcacta ggtcctctta tacttgcccc aacccatcat tggacctaaa ctatccatct 1740 ttcattgcct atttcaacgt gaatagcagc gagttggatc ctacaagagt acaagaattc 1800 aagaggacag tgactaatgt cggagaaggt gtgtcggaat atacagccga gctgactgca 1860 atgcctggac ttaaagttag tgttgttcct gaaaagttgg ttttcaaaga caagtatgaa 1920 aagcaaagct acaagctgag gatagaatgt ccacaactga tgaatgattt cttggttcat 1980 ggttctttaa gctgggtgga aaagggaggt aaatatgtag ttaggagccc aattgttgcc 2040 acaaattctt aagtttgatc ctttgacagg atagtactga ttactgaata ttccactaaa 2100 catgtctttt gagaacatga tatatacata cttgtgaagt gtagttctat ggttcacant 2160 nnaaaaaaaa aaaaaaaaaa aaaaaaaa 2188 12 1481 DNA Artificial Sequence Expression homologous to A thaliana, AAD12260 subtilisin-like protease 12 ctccgatcga aatcctaagt ctaaattgcc aagtttgcta gagccagaaa tctctcaagt 60 gcccagaagc cttgagcgcg aggtgcctgg ccttaatcag aaagctttat tgatgaagaa 120 ttgggaccaa ttccatctaa gtggagaggg atttaccaaa ataattctga tcacaccttt 180 tagtgcaaaa ggaagctaat tggagcaagg tacttcaacg aaggatacgt gactctagca 240 agatctctca attcaagttt ctacacacca cgagacactg atggacatgt ttcccacacg 300 cagttcaagg atcaagtgtt tcccggtatg gaaatggaac agcaaagggt ggatcaccaa 360 aagtaagagt agcagcttac agagtttgct ggcctccaat tatgggcagt gggtgctttg 420 attcagatat cttggttgct tttgatttgg taattgatga tggcgtggac gtgctttcag 480 tctcacttgg aggagatact ggagcatatg tcaatgactc tgtagctatt ggttcatttc 540 atgttgttaa gcacggcatt gttgtcgtta cctctgctgg taactcgtcc tggtcccggt 600 acaatacgaa aaaattgcac cttggctcat aactgttggc gcgagaacta tggattgtca 660 gtttcccagc tatatcattt taggaaacaa aaagcagtac aatttgaaac actgcccaaa 720 tgcatgttct tccctattat aaatgttgct tcagcaaaag ctccccatgc ttcaactgac 780 gatgctctct tatgcaaagc tggggcattg gacccaaaga aggtaaaggt aactatttta 840 gtttgtctaa gaggagataa tacgagggtt gacaagggac agcaagctgc tttggcaggt 900 gcagttggaa cgattctagc caacgattat gcatctggcg atgaaatttt tgctgattct 960 ctctcgtctt acctgctacg caaattagtt acactgatgg acttgaactc tttagttcaa 1020 caagtatacc tacagcttcc attacacatc caacgactta attgggaaca aagccagctc 1080 cagtcatagc agccttttca tcaataggac ctaacactgt tacactggag atccttaagg 1140 ttttacgcag gttcatgatt ttttgacacg acatcttttc ttgaaagatc aggaaacgac 1200 atcttttctt gaaagatcag gaacttgaag tctgaagaag ctatgcttga agaatatgcg 1260 gagcaagttg aagcacaata tagtttttgt tctgttagta gcagtttaaa gattttgtca 1320 tttgtacatc gtgtatagtt ctaatgtctg tttttaggag ttgataaaaa tagtgtcatg 1380 caatttgctt aggtatattt attgacattg tgatccttcg gttttttata atgaacaatg 1440 aaattttgtg gaaaaaaaaa aaaaaaaaaa aaaaaaaaaa a 1481 13 1193 DNA Artificial Sequence Expression homologous to Tomato, CAA07250 serine protease 13 gacagaattg aaaaaggaca agctgtaaag aacgctggag gcgttggcat gattctcatc 60 aatcggcttc aggacggttc aactaaatca gccgatgctc atgtccttcc ggccctggat 120 gtttcatttt ttgatggatt tcaaattact gagtatatga aatcaacaaa gaatcctgtt 180 gctagaatta cattccaagg aacgataata ggcgataaaa atgctccagt gcttgctggt 240 ttttcatctc gcggaccaag cacagctagt cctggaatct tgaaacctga tattattggt 300 cctggtgtta atgtcctagc agcttggcct acttctgtcg aaaacaaaac caacaccaaa 360 tcaacattca acataatttc cggtacctct atgtcatgtc ctcaccttag cggagttgca 420 gcattgttaa aaagcgcgca ccctacttgg tcccctgcag ctattaaatc agcaatcatg 480 acaaccgctg atacagtcaa cctcgccaac aatcccatat tagatgaaat gctccgtcct 540 gcaaacatct ttgccattgg tgcaggacat gtcaatccat cacgagcaaa tgatccagga 600 ctagtttacg atacacaatt caaggattac atatcttatt tatgtggttt gaaatacaca 660 gatcgacaga tgggaagcct tctacaacgc agaacaagtt gctcgaaagt gaaaagtatt 720 cctgaagcac aactcaatta cccttcgttt tccatttcac ttggagcaaa tcaacaaaca 780 tacacaagaa cagtgacaaa cgtcggggag gcaatgtcat cttatcgcgt gaagatagtt 840 tcaccacaaa atgtttccgt tgttgttaag ccttcaactc taaaatttac gaagttgaat 900 cagaagttga cataccgagt gacattttcc acaacaacaa acatcacaaa catggaagtt 960 gttcatggat acttgaaatg gacaagtgat aagcattttg taagaagtcc aattgctgtt 1020 attctacaag agcatgaaac accagaagat tagtgtcttt actttttaat aatttgttca 1080 atttataata accccgtatt aattgattgt atccaaaatg tagaatgagt gcaaaaattg 1140 ctcatgtttt attctactgg tgatatttcc cttgtggtaa aaaaaaaaaa aaa 1193 14 748 DNA Artificial Sequence Expression homologous to Tomato, T06580 subtilisin-like proteinase p69f 14 ggcgtgatta tcggagttat agacactgga attgttcctg accatccttc atttagcgac 60 gttgggatgc ctcctccgcc tgctaaatgg aaaggatttt gtgagtctaa tttcacgacc 120 aagtgtaaca acaaactcat tggagccagg tctttcccgc ttgacaatgg tcccatagat 180 gaaaatggac atggtacgca tacagcaagc acagctgcag gagcctttgt gaaaggtgct 240 aatgtatttg ggaatgccaa tggaacagca gttggtgttg cccctcttgc gtacatagcc 300 atatataagg tatgcggttc tgatggcgtt tgttctgatg ttgaaatttt agctgcgatg 360 gatgtagcta ttgatgatgg cgtagatatt ctatcaatat cccttggtgg aactagtaat 420 ccgttccata atgacaagat tgctcttggg gcgtatagtg caacagaaag aggtattctt 480 gttagttgtt ctgcaggcaa tagtggtcca ttccaacgca ctgtagacaa tgacgcccct 540 tggattctca cagttggcgc tagcactcat gatagaaaac taaaggccac tgttaagctt 600 ggaaataaag aagaatttga aggagaatct gcttatcatc caaagacttc aaactcaaca 660 ttcttcactc tatttgatgt tgaaaagata gtacacgagc aaccagtagc ccctttctgc 720 ataccaggat cactcactga cccttcta 748 15 748 DNA Artificial Sequence Expression homologous to Tomato, T06580 subtilisin-like proteinase p69f 15 gggcgtgatt atcggagtta tagacactgg aattgttcct gaccatcctt catttagcga 60 cgttgggatg cctcctccgc ctgctaaatg gaaaggattt tgtgagtcta atttcacgac 120 caagtgtaac aacaaactca ttggagccag gtctttcccg cttgacaatg gtcccataga 180 tgaaaatgga catggtacgc atacagcaag cacagctgca ggagcctttg tgaaaggtgc 240 taatgtattt gggaatgcca atggaacagc agttggtgtt gcccctcttg cgtacatagc 300 catatataag gtatgcggtt ctgatggcgt ttgttctgat gttgaaattt tagctgcgat 360 ggatgtagct attgatgatg gcgtagatat tctatcaata tcccttggtg gaactagtaa 420 tccgttccat aatgacaaga ttgctcttgg ggcgtatagt gcaacagaaa gaggtattct 480 tgttagttgt tctgcaggca atagtggtcc attccaacgc actgtagaca atgacgcccc 540 ttggattctc acagttggcg ctagcactca tgatagaaaa ctaaaggcca ctgttaagct 600 tggaaataaa gaagaatttg aaggagaatc tgcttatcat ccaaagactt caaactcaac 660 attcttcact ctatttgatg ttgaaaagat agtacacgag caaccagtag cccctttctg 720 cataccagga tcactcactg acccttct 748 16 2538 DNA Artificial Sequence Expression homologous to A thaliana, BAB02339 cucumisin-like serine protease 16 cactttcttc gtcttcttct tctttctccc tcttaatctt cttctttctc aactctttag 60 taatttcagt ccaattggac ggtcataaaa ctttcatagt acacgtgtcc aaatcccata 120 agccccacat ctttactacc cgccaacatt ggtactcctc catcctccga tcagtctctt 180 cttcttccca acactctgcc aaaatccttt actcttacga ttatgctgcc cgtggtttct 240 ctgcccgtct cacttccggg caggctgacc ggctccgccg catgcctggc gtggtctccg 300 tcgtacctga ccgtgcacgt cagcttcaca ccactcacac accgaccttc ttaggcctcg 360 cagattcatt tgggctttgg cccaactccg attacgctga tgacgtcatc gtcggggtgc 420 tcgacacggg catttggccc gaaaggccga gcttttccga cggcgggctt tctgcagtcc 480 cttccggttg gaaaggaaaa tgcgaaactg ggctggactt tcctgcaact tcatgtaacc 540 gtaaaatcat cggtgctcga ttgttttaca aaggttacga agctgatcgt ggaagcccaa 600 ttgacgaatc taaagaatct aaatcgccaa gagatactga aggacatggg actcacactg 660 cttcaactgc agctggatct gttgtagcta acgctagttt ttttcaatac gcaaaaggtg 720 aagctagagg catggctgtg aaagctcgaa tagcagctta taagatctgt tggaaaacag 780 ggtgttttga ttctgatatt ttagctgcaa tggatcaagc tgttgctgat ggagttcacg 840 tgatttctct ttccgttggc gctgacggtt atgcaccgga atatgatgcg gattctattg 900 ctattggagc ttttggtgct tcagaacatg gcgttgttgt ctcttgctct gctggaaact 960 ccggtcccgg tgcttccacc gcggtcaacg ttgcgccgtg gattctcacc gttgctgctt 1020 caacgataga ccgggagttt ccggctgatg ttattttagg agatggcaga atattcggtg 1080 gcgtatccct gtattccggc gatccgctcg gggattcaaa gctacctctt gtttactccg 1140 gtgactgcgg gagtcaactc tgttatccag gaatgctgga tccttcaaag gtagccggaa 1200 aaattgtatt atgtgatcga ggcggcaatg ctagagtaga gaaaggaagt gcagtgaaat 1260 tagccggcgg tgcaggtatg gtcctggcga atttagctga ctccggcgaa gaactcgtcg 1320 ccgattcaca tctcctaccg gcgacaatgg tcggtcaaaa agccggtgac gaaataaggg 1380 attacgtcaa atctgattca tcaccaaaag cgacgattgt tttcaaagga actgtaatcg 1440 gaaaatcacc gtctgctcca cgtattgctg cgttctcagg ccgaggaccc aattatgtaa 1500 caccggagat ccttaaaccg gatgttactg caccaggagt caacatatta gccggttgga 1560 ccgggtccat aggaccaaca gatttggaaa ttgataccag acgagtggaa ttcaacatta 1620 tatctggtac atccatgtct tgtcctcatg ttagcgggtt agctgcttta cttagaaaag 1680 cttaccctaa atggaccaca gcagccatca aatctgccct catgacaaca gcttacaacg 1740 ttgataactc cggcaaaacc tttacagatc tcgcgacagg ccaggaatcg agtccgtttg 1800 ttcacgggtc gggtcatgtg gatccgaaca gagcactaga tccaggtctt gtctacgata 1860 ttgacacgaa ggattacgtg gattttttat gcgccattgg ttatgatccc aaaagaattt 1920 caccgttcgt gaaagatact tcttcagtga attgcagcga aaagaattta gttagtccgg 1980 gggatttgaa ttatccatcg ttctcagttg tatttggcag tgatagtgtg gtgaaaaaca 2040 agcgtgtggt taaaaatgtt ggcaggaata caaatgcggt gtatgaggtg aaaataaatg 2100 cgccgggttc ggtggaggtg aaggtgactc cgactaagct tagttttagc gagaaaaata 2160 agagtttgtc gtatgagatt agttttagca gtaatggaag tgttgggttg gagagagtaa 2220 aaggtcttga atcagcattt gggtcaattg agtggagtga tggaattcac agcgtgagga 2280 gtccaattgc ggtgcattgg ctactccact ctgctacaga atctcagtga gcaatggact 2340 atgaagcaag aagataattg tgctaatctg caaactgtta tgggccagaa acaggaacaa 2400 ggctaagttc agaaaggaaa aggaaatagg gaaggaacat ctatctgttg aaataatgtt 2460 aagaaatttt catcattctt ttcttgttta tgagtattta tcagccacaa aaaaaaaaaa 2520 aaaaaaaaaa aaaaaaaa 2538 17 2426 DNA Artificial Sequence Expression homologous to Alnus glutinosa, S52769 subtilisin-like proteinase ag12 17 ggccaattgt attactatgt atttcttgct ccttactatc ttattactta ctctaaatcc 60 attaactatg gcagagtcag aaacttatat catccatatg gacttatcag ccatgcctaa 120 agctttttct agccatcaga attggtactt gaccactctt gcttctgtat caggtagttc 180 aagtcttgga actgaaagta atagaaattc cttttcctca tcaaaactag tatatgctta 240 cactaacgct attcatggtt ttagtgcaac tctttctcct tctgagctac aagttataaa 300 aaattctcca ggctatcttt cttcaactaa ggacatgaca gttaaaattg acacgacaca 360 cacgtctcaa ttccttggcc taaattccga ttctggtgca tggccaaagt cagactatgg 420 caaagatgtt atagttggat tagttgacac agggatttgg ccagagagta aaagctataa 480 tgataatggg atgactgaag ttccatcaag atggaaagga gaatgtgaaa gtggaactca 540 atttaattcc tctttatgca acaagaaact cattggtgcg cgttacttca acaaaggcct 600 aattgccaat aatccgaata ttaccatctc gatgaattca gctcgtgaca ctgatgggca 660 tggaactcac acatcctcta cagctgcagg aagtcatgta gaatctgcat cttattttgg 720 ctatgcgcgt ggttctgcta cagggatggc accaaaggct catgtggcaa tgtacaaggc 780 tttgtgggaa gaaggtacaa tgttatctga tattctggct gcaattgatc aggcaattga 840 ggatggagtg gatataatat ccttatcatt aggcatagat gatcttgctt tatatgagga 900 tccggtagct attgccacat ttgcagcaat ggagaaagat atatttgttt ccacttcagc 960 tggaaatgaa gggcctgacg atcaggcttt gcacaacgga acaccttggg ttctaactgt 1020 tgctgctggc acagttgatc gcgaatttat cgggacacta agtctgggta atggagtttc 1080 agtcactggt ttatctctct accccgggaa ttccagttca agcgaaagct ccatcgtttt 1140 tctcaagaca tgcctagagg agaaggaact ggagaaaaat gcacacaaat tcgcagtctg 1200 ctatgacacg aacggatcag taagtgacca attgtacaat gtaaaaaaca caaaagttgc 1260 tggtggcatc ttcataacaa attacactga cttggaattc tacctccaaa gcgaattccc 1320 ggctgtgttt ttgaactttg aagatggtga taaagttttg gagtacatca agaatagcca 1380 ttcaccaaaa gcaaggcttg aatttcaagt gacacatctt ggtgctaaac cagcaccaaa 1440 agttgctagc tatagctcaa ggggaccatc agaaagctgc ccttttatcc tcaaacctga 1500 cctgatggct cctggagcct taatattagc ctcatggcct caaaaatcac cggcaactca 1560 aattcgctca ggagagcttt tcagtaactt caacatcata tcaggtacgt caatgtcatg 1620 ccctcatgca gctggtgtag cagcacttct gaaaggagca caccccaaat ggagtcctgc 1680 tgccatccgg tcggccatga tgaccacagc cgacacgatg gataacatgc aaatgcccat 1740 ccgagacata ggtcgcaaca ataatgctgc cagtccccta gccatgggag ctggccgtat 1800 caatccaaat aaggcactag accctggact tatctatgac attacatcac aggactatat 1860 caatctcctc tgtgctctag attttacatc tcaacagata aaagccatta caaggtcctc 1920 tgcttattcc tgttccaact catcattgga tttaaactat ccatcattca taggctattt 1980 caattataac agcagcgagt cagaccctaa aaggatacaa gaattccaga ggacggtgac 2040 taatgtagga gaaggtatgt ctgtatatac agccaaattg acctcaatgg gtgattataa 2100 agctagtgtt gcacctgaca agttggtttt caaagagaag tatgaaaagc aaagctacaa 2160 gctaaggata gaaggtccat tgctagttga tattatcttg tttatggttc tttgagctgg 2220 gtggaaacta gcggtaaata tgttgtaaaa agtcccattg tcgcaactac cataagagtg 2280 gatcctctgt gaggacagaa ctgattatga gtcctgtatt ctgaaaatgt gatacagtga 2340 tgaataattg tgaagttaaa ttcaaaaaaa aatcttttca gttagttaaa actaacttgc 2400 tgattaaaaa aaaaaaaaaa aaaaaa 2426 18 737 PRT Nicotiana benthamiana 18 Ala Asn Cys Ile Thr Met Tyr Phe Leu Leu Leu Thr Ile Leu Leu Leu 1 5 10 15 Thr Leu Asn Pro Leu Thr Met Ala Glu Ser Glu Thr Tyr Ile Ile His 20 25 30 Met Asp Leu Ser Ala Met Pro Lys Ala Phe Ser Ser His Gln Asn Trp 35 40 45 Tyr Leu Thr Thr Leu Ala Ser Val Ser Gly Ser Ser Ser Leu Gly Thr 50 55 60 Glu Ser Asn Arg Asn Ser Phe Ser Ser Ser Lys Leu Val Tyr Ala Tyr 65 70 75 80 Thr Asn Ala Ile His Gly Phe Ser Ala Thr Leu Ser Pro Ser Glu Leu 85 90 95 Gln Val Ile Lys Asn Ser Pro Gly Tyr Leu Ser Ser Thr Lys Asp Met 100 105 110 Thr Val Lys Ile Asp Thr Thr His Thr Ser Gln Phe Leu Gly Leu Asn 115 120 125 Ser Asp Ser Gly Ala Trp Pro Lys Ser Asp Tyr Gly Lys Asp Val Ile 130 135 140 Val Gly Leu Val Asp Thr Gly Ile Trp Pro Glu Ser Lys Ser Tyr Asn 145 150 155 160 Asp Asn Gly Met Thr Glu Val Pro Ser Arg Trp Lys Gly Glu Cys Glu 165 170 175 Ser Gly Thr Gln Phe Asn Ser Ser Leu Cys Asn Lys Lys Leu Ile Gly 180 185 190 Ala Arg Tyr Phe Asn Lys Gly Leu Ile Ala Asn Asn Pro Asn Ile Thr 195 200 205 Ile Ser Met Asn Ser Ala Arg Asp Thr Asp Gly His Gly Thr His Thr 210 215 220 Ser Ser Thr Ala Ala Gly Ser His Val Glu Ser Ala Ser Tyr Phe Gly 225 230 235 240 Tyr Ala Arg Gly Ser Ala Thr Gly Met Ala Pro Lys Ala His Val Ala 245 250 255 Met Tyr Lys Ala Leu Trp Glu Glu Gly Thr Met Leu Ser Asp Ile Leu 260 265 270 Ala Ala Ile Asp Gln Ala Ile Glu Asp Gly Val Asp Ile Ile Ser Leu 275 280 285 Ser Leu Gly Ile Asp Asp Leu Ala Leu Tyr Glu Asp Pro Val Ala Ile 290 295 300 Ala Thr Phe Ala Ala Met Glu Lys Asp Ile Phe Val Ser Thr Ser Ala 305 310 315 320 Gly Asn Glu Gly Pro Asp Asp Gln Ala Leu His Asn Gly Thr Pro Trp 325 330 335 Val Leu Thr Val Ala Ala Gly Thr Val Asp Arg Glu Phe Ile Gly Thr 340 345 350 Leu Ser Leu Gly Asn Gly Val Ser Val Thr Gly Leu Ser Leu Tyr Pro 355 360 365 Gly Asn Ser Ser Ser Ser Glu Ser Ser Ile Val Phe Leu Lys Thr Cys 370 375 380 Leu Glu Glu Lys Glu Leu Glu Lys Asn Ala His Lys Phe Ala Val Cys 385 390 395 400 Tyr Asp Thr Asn Gly Ser Val Ser Asp Gln Leu Tyr Asn Val Lys Asn 405 410 415 Thr Lys Val Ala Gly Gly Ile Phe Ile Thr Asn Tyr Thr Asp Leu Glu 420 425 430 Phe Tyr Leu Gln Ser Glu Phe Pro Ala Val Phe Leu Asn Phe Glu Asp 435 440 445 Gly Asp Lys Val Leu Glu Tyr Ile Lys Asn Ser His Ser Pro Lys Ala 450 455 460 Arg Leu Glu Phe Gln Val Thr His Leu Gly Ala Lys Pro Ala Pro Lys 465 470 475 480 Val Ala Ser Tyr Ser Ser Arg Gly Pro Ser Glu Ser Cys Pro Phe Ile 485 490 495 Leu Lys Pro Asp Leu Met Ala Pro Gly Ala Leu Ile Leu Ala Ser Trp 500 505 510 Pro Gln Lys Ser Pro Ala Thr Gln Ile Arg Ser Gly Glu Leu Phe Ser 515 520 525 Asn Phe Asn Ile Ile Ser Gly Thr Ser Met Ser Cys Pro His Ala Ala 530 535 540 Gly Val Ala Ala Leu Leu Lys Gly Ala His Pro Lys Trp Ser Pro Ala 545 550 555 560 Ala Ile Arg Ser Ala Met Met Thr Thr Ala Asp Thr Met Asp Asn Met 565 570 575 Gln Met Pro Ile Arg Asp Ile Gly Arg Asn Asn Asn Ala Ala Ser Pro 580 585 590 Leu Ala Met Gly Ala Gly Arg Ile Asn Pro Asn Lys Ala Leu Asp Pro 595 600 605 Gly Leu Ile Tyr Asp Ile Thr Ser Gln Asp Tyr Ile Asn Leu Leu Cys 610 615 620 Ala Leu Asp Phe Thr Ser Gln Gln Ile Lys Ala Ile Thr Arg Ser Ser 625 630 635 640 Ala Tyr Ser Cys Ser Asn Ser Ser Leu Asp Leu Asn Tyr Pro Ser Phe 645 650 655 Ile Gly Tyr Phe Asn Tyr Asn Ser Ser Glu Ser Asp Pro Lys Arg Ile 660 665 670 Gln Glu Phe Gln Arg Thr Val Thr Asn Val Gly Glu Gly Met Ser Val 675 680 685 Tyr Thr Ala Lys Leu Thr Ser Met Gly Asp Tyr Lys Ala Ser Val Ala 690 695 700 Pro Asp Lys Leu Val Phe Lys Glu Lys Tyr Glu Lys Gln Ser Tyr Lys 705 710 715 720 Leu Arg Ile Glu Gly Pro Leu Leu Val Asp Ile Ile Leu Phe Met Val 725 730 735 Leu 19 289 PRT Nicotiana benthamiana 19 Val Ser Thr Gln Ser Ala Ile Thr Ala Gly Asp Asp Gly Ile Ser Glu 1 5 10 15 Val Pro Ser Arg Trp Lys Gly Glu Cys Glu Ser Gly Thr Glu Phe Asn 20 25 30 Ser Ser Leu Cys Asn Lys Lys Leu Ile Gly Ala Arg Tyr Phe Asn Lys 35 40 45 Gly Leu Leu Ala Asn Asn Pro Asn Leu Asn Ile Ser Met Asn Ser Ser 50 55 60 Arg Asp Thr Asp Gly His Gly Thr His Thr Ser Ser Thr Ala Ala Gly 65 70 75 80 Ser Tyr Val Glu Gly Ala Ser Tyr Phe Gly Tyr Ala Thr Gly Thr Ala 85 90 95 Ile Gly Ile Ala Pro Lys Ala His Val Ala Met Tyr Lys Ala Leu Trp 100 105 110 Glu Glu Gly Val Tyr Leu Ser Asp Val Leu Ala Ala Ile Asp Gln Ala 115 120 125 Ile Thr Asp Gly Val Asp Val Leu Ser Leu Ser Leu Gly Ile Asp Ala 130 135 140 Ile Pro Leu His Glu Asp Pro Val Ala Ile Ala Ala Phe Ala Ala Leu 145 150 155 160 Glu Lys Gly Ile Phe Val Ser Thr Ser Ala Gly Asn Glu Gly Pro Tyr 165 170 175 Tyr Glu Thr Leu His Asn Gly Thr Pro Trp Val Leu Thr Val Ala Ala 180 185 190 Gly Thr Val Asp Arg Glu Phe Ile Gly Thr Leu Thr Leu Gly Asn Gly 195 200 205 Val Ser Val Pro Gly Leu Ser Leu Tyr Pro Gly Asn Ser Ser Ser Ser 210 215 220 Glu Ser Ser Leu Val Tyr Val Glu Cys Gln Asp Asp Lys Glu Leu Gln 225 230 235 240 Lys Asn Ala His Lys Phe Val Val Cys Leu Asp Lys Asn Asp Ser Val 245 250 255 Gly Glu His Val Tyr Asn Val Arg Asn Ser Lys Val Ala Gly Ala Val 260 265 270 Phe Ile Thr Asn Thr Thr Asp Leu Glu Phe Tyr Leu Gln Ser Glu Phe 275 280 285 Pro 20 683 PRT Nicotiana benthamiana misc_feature (7)..(7) Xaa can be any naturally occurring amino acid 20 Thr Pro Arg Pro Thr Arg Xaa Pro Thr Arg Pro Pro Thr Arg Pro Leu 1 5 10 15 Ser Pro Ser Glu Tyr Lys Ala Ile Lys Asn Ser Leu Gly Tyr Val Ser 20 25 30 Ser Met Glu Asp Arg Thr Val Lys Ile His Thr Thr His Ser Ser His 35 40 45 Phe Leu Gly Leu Ser Ser Met Tyr Gly Ser Trp Pro Lys Ser Asn Tyr 50 55 60 Gly Lys Gly Val Ile Ile Gly Val Val Asp Thr Gly Val Trp Pro Glu 65 70 75 80 Ile Lys Ser Phe Asp Asp Asp Gly Met Ser Gln Val Pro Ser Arg Trp 85 90 95 Lys Gly Ile Cys Gln Thr Gly Thr Gln Phe Asn Ser Ser Leu Cys Asn 100 105 110 Lys Lys Leu Ile Gly Ala Arg Tyr Phe Asn Lys Gly Leu Leu Ser Lys 115 120 125 Val Lys Asn Leu Thr Ile Met Ile Asn Ser Ala Arg Asp Thr Glu Gly 130 135 140 His Gly Thr His Thr Ser Ser Thr Ala Ala Gly Ser Leu Val Lys Gly 145 150 155 160 Ala Ser Tyr Phe Gly Tyr Ala Pro Gly Phe Ala Ile Gly Val Ala Pro 165 170 175 Met Ala His Val Ala Val Tyr Lys Ala Leu Trp Asp Gly Ala Gly Thr 180 185 190 Ile Ser Asp Ile Leu Ala Ala Leu Asp Gln Ala Ile Ala Asp Gly Cys 195 200 205 Asp Ile Leu Ser Leu Ser Phe Gly Ala Val Ser Pro Phe Pro Leu Tyr 210 215 220 Ile Asp Pro Ile Ser Ile Ala Ser Phe Ser Ala Met Glu Lys Gly Ile 225 230 235 240 Phe Val Ser Val Ser Ala Gly Asn Glu Gly Pro Phe Asp Gln Ser Leu 245 250 255 Ser Asn Glu Ala Pro Trp Phe Leu Ser Val Ala Ala Ser Thr Val Asp 260 265 270 Arg Asp Val Ile Arg Ile Leu Thr Leu Gly Asn Gly Val Ser Val Thr 275 280 285 Gly Leu Ser Leu Tyr Pro Gly Asn Ser Thr Ser Asp Ile Ser Val Ile 290 295 300 Leu Val Lys Asn Cys Leu Asp Lys Gln Glu Leu Gln Asn Val Thr Asp 305 310 315 320 Lys Phe Val Val Cys Ile Asp Lys Asn Ala Leu Val Gly Lys Gln Val 325 330 335 Glu Ser Val Arg His Ser Asn Ala Ala Gly Ala Val Phe Ile Thr Asn 340 345 350 Asp Phe Val Thr Asp Leu Gly Glu Tyr Leu Lys Thr Glu Phe Pro Ser 355 360 365 Val Phe Leu Asn Phe Gln Asn Gly Asp Gln Val Leu Lys Tyr Val Asn 370 375 380 Ser Thr Ser Ser Pro Lys Ala Lys Ile Gly Leu Gln Gly Thr Leu Ile 385 390 395 400 Gly Val Glu Arg Ala Pro Ala Val Ala His Phe Ser Ser Arg Gly Pro 405 410 415 Ser Met Thr Cys Pro Phe Ile Leu Lys Pro Asp Leu Met Ala Pro Gly 420 425 430 His Leu Ile Leu Ala Ser Trp Ser Pro Leu Ser Ser Val Ser Pro Tyr 435 440 445 Thr Glu Leu His Asn Ile Phe Asn Ile Ile Ser Gly Thr Ser Met Ser 450 455 460 Cys Pro His Ala Ala Gly Val Ala Ala Leu Val Lys Gly Thr His Pro 465 470 475 480 Glu Trp Ser Pro Ala Ala Ile Arg Ser Ala Met Met Thr Thr Ala Asp 485 490 495 Val Leu Asp Asn Thr Gln Ser Pro Ile Gln Asp Ile Gly Arg Pro Glu 500 505 510 Asn Ala Ala Ala Thr Pro Leu Ala Met Gly Ala Gly His Ile Asn Pro 515 520 525 Asn Lys Ala Ile Asp Pro Gly Leu Ile Tyr Asp Thr Thr Pro Gln Asp 530 535 540 Tyr Ile Asn Leu Leu Cys Ala Leu Asn Leu Thr Ser Glu Gln Ile Lys 545 550 555 560 Thr Ile Thr Arg Ser Ser Tyr Thr Cys Pro Asn Pro Ser Leu Asp Leu 565 570 575 Asn Tyr Pro Ser Phe Ile Ala Tyr Phe Asn Val Asn Ser Ser Glu Leu 580 585 590 Asp Pro Thr Arg Val Gln Glu Phe Lys Arg Thr Val Thr Asn Val Gly 595 600 605 Glu Gly Val Ser Glu Tyr Thr Ala Glu Leu Thr Ala Met Pro Gly Leu 610 615 620 Lys Val Ser Val Val Pro Glu Lys Leu Val Phe Lys Asp Lys Tyr Glu 625 630 635 640 Lys Gln Ser Tyr Lys Leu Arg Ile Glu Cys Pro Gln Leu Met Asn Asp 645 650 655 Phe Leu Val His Gly Ser Leu Ser Trp Val Glu Lys Gly Gly Lys Tyr 660 665 670 Val Val Arg Ser Pro Ile Val Ala Thr Asn Ser 675 680 21 770 PRT Nicotiana benthamiana misc_feature (211)..(211) Xaa can be any naturally occurring amino acid 21 Val Phe Pro Phe Phe Phe Ile Ile Ile Ser Phe Cys Leu Thr Pro Val 1 5 10 15 Thr Ile Ser Val Gln Ser Asp Gly His Glu Thr Phe Ile Ile His Val 20 25 30 Ser Lys Ser Asp Lys Pro Arg Val Phe Thr Thr His His His Trp Tyr 35 40 45 Ser Ser Ile Ile Arg Ser Val Ser Gln His Pro Ser Lys Ile Leu Tyr 50 55 60 Thr Tyr Glu Arg Ala Ala Val Gly Phe Ser Ala Arg Leu Thr Ala Ala 65 70 75 80 Gln Ala Asp Gln Leu Arg Arg Ile Pro Gly Val Ile Ser Val Leu Pro 85 90 95 Asp Glu Val Arg His Leu His Thr Thr His Thr Pro Thr Phe Leu Gly 100 105 110 Leu Ala Asp Ser Phe Gly Leu Trp Pro Asn Ser Asp Tyr Ala Asp Asp 115 120 125 Val Ile Val Gly Val Leu Asp Thr Gly Ile Trp Pro Glu Arg Pro Ser 130 135 140 Phe Ser Asp Glu Gly Leu Ser Thr Val Pro Ser Ser Trp Lys Gly Lys 145 150 155 160 Cys Val Thr Gly Pro Asp Phe Pro Glu Thr Ser Cys Asn Lys Lys Ile 165 170 175 Ile Gly Ala Gln Met Phe Tyr Lys Gly Tyr Glu Ala Lys His Gly Pro 180 185 190 Met Asp Glu Ser Lys Glu Ser Lys Ser Pro Arg Asp Thr Glu Gly His 195 200 205 Gly Thr Xaa Thr Ala Ser Thr Ala Ala Gly Ser Leu Val Ala Asn Ala 210 215 220 Ser Phe Tyr Gln Tyr Ala Lys Gly Glu Ala Arg Gly Met Ala Ile Lys 225 230 235 240 Ala Arg Ile Ala Ala Tyr Lys Ile Cys Trp Lys Asn Gly Cys Phe Asn 245 250 255 Ser Asp Ile Leu Ala Ala Met Asp Gln Ala Val Asp Asp Gly Val His 260 265 270 Val Ile Ser Leu Ser Val Gly Ala Asn Gly Tyr Ala Pro His Tyr Leu 275 280 285 Tyr Asp Ser Ile Ala Ile Gly Ala Phe Gly Ala Ser Glu His Gly Val 290 295 300 Leu Val Ser Cys Ser Ala Gly Asn Ser Gly Pro Gly Ala Tyr Thr Ala 305 310 315 320 Val Asn Ile Ala Pro Trp Met Leu Thr Val Gly Ala Ser Thr Ile Asp 325 330 335 Arg Glu Phe Pro Ala Asp Val Ile Leu Gly Asp Asn Arg Ile Phe Gly 340 345 350 Gly Val Ser Leu Tyr Ser Gly Asn Pro Leu Thr Asp Ala Lys Leu Pro 355 360 365 Val Val Tyr Ser Gly Asp Cys Gly Ser Lys Tyr Cys Tyr Pro Gly Lys 370 375 380 Leu Asp Pro Lys Lys Val Ala Gly Lys Ile Val Leu Cys Asp Arg Gly 385 390 395 400 Gly Asn Ala Arg Val Glu Lys Gly Ser Ala Val Lys Gln Ala Gly Gly 405 410 415 Val Gly Met Ile Leu Ala Asn Leu Ala Asp Ser Gly Glu Glu Leu Val 420 425 430 Ala Asp Ser His Leu Leu Pro Ala Thr Met Val Gly Gln Lys Ala Gly 435 440 445 Asp Lys Ile Arg His Tyr Val Thr Ser Asp Pro Ser Pro Thr Ala Thr 450 455 460 Ile Val Phe Arg Gly Thr Val Ile Gly Lys Ser Pro Ala Ala Pro Arg 465 470 475 480 Val Ala Ala Phe Ser Ser Arg Gly Pro Asn His Leu Thr Pro Glu Ile 485 490 495 Leu Lys Pro Asp Val Ile Ala Pro Gly Val Asn Ile Leu Ala Gly Trp 500 505 510 Thr Gly Ser Val Gly Pro Thr Asp Leu Asp Ile Asp Thr Arg Arg Val 515 520 525 Glu Phe Asn Ile Ile Ser Gly Thr Ser Met Ser Cys Pro His Val Gly 530 535 540 Gly Leu Ala Ala Leu Leu Arg Arg Ala His Pro Lys Trp Thr Pro Ala 545 550 555 560 Ala Val Lys Ser Ala Leu Met Thr Thr Ala Tyr Asn Leu Asp Asn Ser 565 570 575 Gly Lys Val Phe Thr Asp Leu Ala Thr Gly Gln Glu Ser Thr Pro Phe 580 585 590 Val His Gly Ser Gly His Val Asp Pro Asn Arg Ala Leu Asp Pro Gly 595 600 605 Leu Ile Tyr Asp Ile Glu Thr Ser Asp Tyr Val Asn Phe Leu Cys Ser 610 615 620 Ile Gly Tyr Asp Gly Asp Asp Val Ala Val Phe Ala Arg Asp Ser Ser 625 630 635 640 Arg Val Asn Cys Ser Glu Arg Ser Leu Ala Thr Pro Gly Asp Leu Asn 645 650 655 Tyr Pro Ser Phe Ser Val Val Phe Thr Gly Glu Ser Asn Gly Val Val 660 665 670 Lys Tyr Lys Arg Val Val Asn Asn Val Gly Lys Asn Thr Asp Ala Val 675 680 685 Tyr Glu Val Lys Val Asn Ala Pro Ser Ser Val Glu Val Asn Val Ser 690 695 700 Pro Ala Lys Leu Val Phe Ser Glu Glu Lys Gln Ser Leu Ser Tyr Glu 705 710 715 720 Ile Ser Leu Lys Ser Lys Lys Ser Gly Asp Leu Gln Met Val Lys Gly 725 730 735 Ile Glu Ser Ala Phe Gly Ser Ile Glu Trp Ser Asp Gly Ile His Asn 740 745 750 Val Arg Ser Pro Ile Ala Val Arg Trp Arg His Tyr Ser Asp Ala Ala 755 760 765 Ser Met 770 22 770 PRT Nicotiana benthamiana 22 Pro Thr Arg Pro Val Phe Pro Phe Phe Phe Ile Ile Ile Ser Phe Cys 1 5 10 15 Leu Thr Pro Val Thr Ile Ser Val Gln Ser Asp Gly His Glu Thr Phe 20 25 30 Ile Ile His Val Ser Lys Ser Asp Lys Pro Arg Val Phe Thr Thr His 35 40 45 His His Trp Tyr Ser Ser Ile Ile Arg Ser Val Ser Gln His Pro Ser 50 55 60 Lys Ile Leu Tyr Thr Tyr Glu Arg Ala Ala Val Gly Phe Ser Ala Arg 65 70 75 80 Leu Thr Ala Ala Gln Ala Asp Gln Leu Arg Arg Ile Pro Gly Val Ile 85 90 95 Ser Val Leu Pro Asp Glu Val Arg His Leu His Thr Thr His Thr Pro 100 105 110 Thr Phe Leu Gly Leu Ala Asp Ser Phe Gly Leu Trp Pro Asn Ser Asp 115 120 125 Tyr Ala Asp Asp Val Ile Val Gly Val Leu Asp Thr Gly Ile Trp Pro 130 135 140 Glu Arg Pro Ser Phe Ser Asp Glu Gly Leu Ser Thr Val Pro Ser Ser 145 150 155 160 Trp Lys Gly Lys Cys Val Thr Gly Pro Asp Phe Pro Glu Thr Ser Cys 165 170 175 Asn Lys Lys Ile Ile Gly Ala Gln Met Phe Tyr Lys Gly Tyr Glu Ala 180 185 190 Lys His Gly Pro Met Asp Glu Ser Lys Glu Ser Lys Ser Pro Arg Asp 195 200 205 Thr Glu Gly His Gly Thr His Thr Ala Ser Thr Ala Ala Gly Ser Leu 210 215 220 Val Ala Asn Ala Ser Phe Tyr Gln Tyr Ala Lys Gly Met Ala Ile Lys 225 230 235 240 Ala Arg Ile Ala Ala Tyr Lys Ile Cys Trp Lys Asn Gly Cys Phe Asn 245 250 255 Ser Asp Ile Leu Ala Ala Met Asp Gln Ala Val Asp Asp Gly Val His 260 265 270 Val Ile Ser Leu Ser Val Gly Ala Asn Gly Tyr Ala Pro His Tyr Leu 275 280 285 Tyr Asp Ser Ile Ala Ile Gly Ala Phe Gly Ala Ser Glu His Gly Val 290 295 300 Leu Val Ser Cys Ser Ala Gly Asn Ser Gly Pro Gly Ala Tyr Thr Ala 305 310 315 320 Val Asn Ile Ala Pro Trp Met Leu Thr Val Gly Ala Ser Thr Ile Asp 325 330 335 Arg Glu Phe Pro Ala Asp Val Ile Leu Gly Asp Asn Arg Ile Phe Gly 340 345 350 Gly Val Ser Leu Tyr Ser Gly Asn Pro Leu Thr Asp Ala Lys Leu Pro 355 360 365 Val Val Tyr Ser Gly Asp Cys Gly Ser Lys Tyr Cys Tyr Pro Gly Lys 370 375 380 Leu Asp Pro Lys Lys Val Ala Gly Lys Ile Val Leu Cys Asp Arg Gly 385 390 395 400 Gly Asn Ala Arg Val Glu Lys Gly Ser Ala Val Lys Gln Ala Gly Gly 405 410 415 Val Gly Met Ile Leu Ala Asn Leu Ala Asp Ser Gly Glu Glu Leu Val 420 425 430 Ala Asp Ser His Leu Leu Pro Ala Thr Met Val Gly Gln Lys Ala Gly 435 440 445 Asp Lys Ile Arg His Tyr Val Thr Ser Asp Pro Ser Pro Thr Ala Thr 450 455 460 Ile Val Phe Arg Gly Thr Val Ile Gly Lys Ser Pro Ala Ala Pro Arg 465 470 475 480 Val Ala Ala Phe Ser Ser Arg Gly Pro Asn His Leu Thr Pro Glu Ile 485 490 495 Leu Lys Pro Asp Val Ile Ala Pro Gly Val Asn Ile Leu Ala Gly Trp 500 505 510 Thr Gly Ser Val Gly Pro Thr Asp Leu Asp Ile Asp Thr Arg Arg Val 515 520 525 Glu Phe Asn Ile Ile Ser Gly Thr Ser Met Ser Cys Pro His Val Gly 530 535 540 Gly Leu Ala Ala Leu Leu Arg Arg Ala His Pro Lys Trp Thr Pro Ala 545 550 555 560 Ala Val Lys Ser Ala Leu Met Thr Thr Ala Tyr Asn Leu Asp Asn Ser 565 570 575 Gly Lys Val Phe Thr Asp Leu Ala Thr Gly Gln Glu Ser Thr Pro Phe 580 585 590 Val His Gly Ser Gly His Val Asp Pro Asn Arg Ala Leu Asp Pro Gly 595 600 605 Leu Ile Tyr Asp Ile Glu Thr Ser Asp Tyr Val Asn Phe Leu Cys Ser 610 615 620 Met Ala Tyr Asp Gly Asp Asp Val Ala Val Phe Ala Arg Asp Ser Ser 625 630 635 640 Arg Val Asn Cys Ser Glu Arg Ser Leu Ala Thr Pro Gly Asp Leu Asn 645 650 655 Tyr Pro Ser Phe Ser Val Val Phe Thr Gly Glu Ser Asn Gly Val Val 660 665 670 Lys Tyr Lys Arg Val Val Asn Asn Val Gly Lys Asn Thr Asp Ala Val 675 680 685 Tyr Glu Val Lys Val Asn Ala Pro Ser Ser Val Glu Val Asn Val Ser 690 695 700 Pro Ala Lys Leu Val Phe Ser Glu Glu Lys Gln Ser Leu Ser Tyr Glu 705 710 715 720 Ile Ser Leu Lys Ser Lys Lys Ser Gly Asp Leu Gln Met Val Lys Gly 725 730 735 Ile Glu Ser Ala Phe Gly Ser Ile Glu Trp Ser Asp Gly Ile His Asn 740 745 750 Val Arg Ser Pro Ile Ala Val Arg Trp Arg His Tyr Ser Asp Ala Ala 755 760 765 Ser Met 770 23 775 PRT Nicotiana benthamiana 23 Leu Ser Ser Ser Ser Ser Ser Phe Ser Leu Leu Ile Phe Phe Phe Leu 1 5 10 15 Asn Ser Leu Val Ile Ser Val Gln Leu Asp Gly His Lys Thr Phe Ile 20 25 30 Val His Val Ser Lys Ser His Lys Pro His Ile Phe Thr Thr Arg Gln 35 40 45 His Trp Tyr Ser Ser Ile Leu Arg Ser Val Ser Ser Ser Ser Gln His 50 55 60 Ser Ala Lys Ile Leu Tyr Ser Tyr Asp Tyr Ala Ala Arg Gly Phe Ser 65 70 75 80 Ala Arg Leu Thr Ser Gly Gln Ala Asp Arg Leu Arg Arg Met Pro Gly 85 90 95 Val Val Ser Val Val Pro Asp Arg Ala Arg Gln Leu His Thr Thr His 100 105 110 Thr Pro Thr Phe Leu Gly Leu Ala Asp Ser Phe Gly Leu Trp Pro Asn 115 120 125 Ser Asp Tyr Ala Asp Asp Val Ile Val Gly Val Leu Asp Thr Gly Ile 130 135 140 Trp Pro Glu Arg Pro Ser Phe Ser Asp Gly Gly Leu Ser Ala Val Pro 145 150 155 160 Ser Gly Trp Lys Gly Lys Cys Glu Thr Gly Leu Asp Phe Pro Ala Thr 165 170 175 Ser Cys Asn Arg Lys Ile Ile Gly Ala Arg Leu Phe Tyr Lys Gly Tyr 180 185 190 Glu Ala Asp Arg Gly Ser Pro Ile Asp Glu Ser Lys Glu Ser Lys Ser 195 200 205 Pro Arg Asp Thr Glu Gly His Gly Thr His Thr Ala Ser Thr Ala Ala 210 215 220 Gly Ser Val Val Ala Asn Ala Ser Phe Phe Gln Tyr Ala Lys Gly Glu 225 230 235 240 Ala Arg Gly Met Ala Val Lys Ala Arg Ile Ala Ala Tyr Lys Ile Cys 245 250 255 Trp Lys Thr Gly Cys Phe Asp Ser Asp Ile Leu Ala Ala Met Asp Gln 260 265 270 Ala Val Ala Asp Gly Val His Val Ile Ser Leu Ser Val Gly Ala Asp 275 280 285 Gly Tyr Ala Pro Glu Tyr Asp Ala Asp Ser Ile Ala Ile Gly Ala Phe 290 295 300 Gly Ala Ser Glu His Gly Val Val Val Ser Cys Ser Ala Gly Asn Ser 305 310 315 320 Gly Pro Gly Ala Ser Thr Ala Val Asn Val Ala Pro Trp Ile Leu Thr 325 330 335 Val Ala Ala Ser Thr Ile Asp Arg Glu Phe Pro Ala Asp Val Ile Leu 340 345 350 Gly Asp Gly Arg Ile Phe Gly Gly Val Ser Leu Tyr Ser Gly Asp Pro 355 360 365 Leu Gly Asp Ser Lys Leu Pro Leu Val Tyr Ser Gly Asp Cys Gly Ser 370 375 380 Gln Leu Cys Tyr Pro Gly Met Leu Asp Pro Ser Lys Val Ala Gly Lys 385 390 395 400 Ile Val Leu Cys Asp Arg Gly Gly Asn Ala Arg Val Glu Lys Gly Ser 405 410 415 Ala Val Lys Leu Ala Gly Gly Ala Gly Met Val Leu Ala Asn Leu Ala 420 425 430 Asp Ser Gly Glu Glu Leu Val Ala Asp Ser His Leu Leu Pro Ala Thr 435 440 445 Met Val Gly Gln Lys Ala Gly Asp Glu Ile Arg Asp Tyr Val Lys Ser 450 455 460 Asp Ser Ser Pro Lys Ala Thr Ile Val Phe Lys Gly Thr Val Ile Gly 465 470 475 480 Lys Ser Pro Ser Ala Pro Arg Ile Ala Ala Phe Ser Gly Arg Gly Pro 485 490 495 Asn Tyr Val Thr Pro Glu Ile Leu Lys Pro Asp Val Thr Ala Pro Gly 500 505 510 Val Asn Ile Leu Ala Gly Trp Thr Gly Ser Ile Gly Pro Thr Asp Leu 515 520 525 Glu Ile Asp Thr Arg Arg Val Glu Phe Asn Ile Ile Ser Gly Thr Ser 530 535 540 Met Ser Cys Pro His Val Ser Gly Leu Ala Ala Leu Leu Arg Lys Ala 545 550 555 560 Tyr Pro Lys Trp Thr Thr Ala Ala Ile Lys Ser Ala Leu Met Thr Thr 565 570 575 Ala Tyr Asn Val Asp Asn Ser Gly Lys Thr Phe Thr Asp Leu Ala Thr 580 585 590 Gly Gln Glu Ser Ser Pro Phe Val His Gly Ser Gly His Val Asp Pro 595 600 605 Asn Arg Ala Leu Asp Pro Gly Leu Val Tyr Asp Ile Asp Thr Lys Asp 610 615 620 Tyr Val Asp Phe Leu Cys Ala Ile Gly Tyr Asp Pro Lys Arg Ile Ser 625 630 635 640 Pro Phe Val Lys Asp Thr Ser Ser Val Asn Cys Ser Glu Lys Asn Leu 645 650 655 Val Ser Pro Gly Asp Leu Asn Tyr Pro Ser Phe Ser Val Val Phe Gly 660 665 670 Ser Asp Ser Val Val Lys Asn Lys Arg Val Val Lys Asn Val Gly Arg 675 680 685 Asn Thr Asn Ala Val Tyr Glu Val Lys Ile Asn Ala Pro Gly Ser Val 690 695 700 Glu Val Lys Val Thr Pro Thr Lys Leu Ser Phe Ser Glu Lys Asn Lys 705 710 715 720 Ser Leu Ser Tyr Glu Ile Ser Phe Ser Ser Asn Gly Ser Val Gly Leu 725 730 735 Glu Arg Val Lys Gly Leu Glu Ser Ala Phe Gly Ser Ile Glu Trp Ser 740 745 750 Asp Gly Ile His Ser Val Arg Ser Pro Ile Ala Val His Trp Leu Leu 755 760 765 His Ser Ala Thr Glu Ser Gln 770 775 24 398 PRT Nicotiana benthamiana 24 Gly Val Ile Ile Gly Val Ile Asp Thr Gly Ile Phe Pro Asp His Pro 1 5 10 15 Ser Phe Ser Asp Val Gly Met Ser Pro Pro Pro Ala Lys Trp Lys Gly 20 25 30 Phe Cys Glu Ser Asn Phe Thr Thr Lys Cys Asn Asn Lys Ile Ile Gly 35 40 45 Leu Arg Ser Phe Arg Leu Ser Glu Asp Thr Pro Ile Asp Thr Asp Gly 50 55 60 His Gly Thr His Thr Ala Ser Thr Ala Ala Gly Ala Phe Val Lys Gly 65 70 75 80 Ala Asn Phe Phe Gly Asn Ala Asn Gly Thr Ala Val Gly Val Ala Pro 85 90 95 Leu Ala His Met Ala Ile Tyr Lys Val Cys Ser Phe Ala Thr Cys Ser 100 105 110 Glu Thr Asp Ala Leu Ala Ala Met Asp Ala Ala Ile Asp Asp Gly Val 115 120 125 Asp Ile Ile Ser Ala Ser Leu Gly Gly Phe Thr Asn Ala Pro Leu His 130 135 140 Asp Asp Pro Ile Ser Leu Gly Ala Tyr Ser Ala Thr Glu Lys Gly Ile 145 150 155 160 Leu Ala Ser Ala Ser Ala Gly Asn Ser Glu Phe Asp Asn Pro Val Ala 165 170 175 Asn Asn Ala Pro Trp Ile Leu Thr Val Gly Ala Ser Thr His Asp Arg 180 185 190 Lys Leu Lys Ala Thr Val Lys Leu Gly Asn Lys Glu Glu Phe Glu Gly 195 200 205 Glu Ser Ala Asp Gln Pro Lys Thr Ser Asn Ser Thr Phe Ile Ala Leu 210 215 220 Phe Asp Ala Gly Lys Asn Ala Ser Asp Gln Asp Ala Pro Phe Cys Arg 225 230 235 240 Ser Trp Ala Met Thr Asp Pro Ala Ile Lys Gly Lys Ile Val Leu Cys 245 250 255 Gln Lys Asp Pro Ser Ser Leu Thr Ser Ser Gln Gly Arg Asn Val Lys 260 265 270 Asp Ala Gly Gly Val Gly Met Ile Leu Ile Asn Asn Pro Glu Asp Gly 275 280 285 Val Thr Lys Ser Ala Thr Ala His Val Leu Pro Ala Leu Asp Val Ser 290 295 300 His Glu Glu Gly Glu Lys Ile Lys Ala Tyr Ile Asn Ser Thr Ser Asn 305 310 315 320 Pro Ile Ala Ala Ile Thr Phe Gln Gly Thr Val Ile Gly Asp Lys Asn 325 330 335 Ala Pro Ile Val Ala Ser Phe Ser Ala Arg Gly Pro Ser Arg Ala Asn 340 345 350 Pro Gly Ile Leu Lys Pro Asp Ile Ile Gly Pro Gly Val Asn Ile Leu 355 360 365 Ala Ala Trp Pro Thr Thr Val Asn Ile Pro Asn Lys Asn Thr Asn Ser 370 375 380 Gly Phe Asn Ile Ile Ser Gly Thr Ser Met Ser Cys Pro His 385 390 395 25 398 PRT Nicotiana benthamiana 25 Gly Val Ile Ile Gly Val Ile Asp Thr Gly Ile Val Pro Asp His Pro 1 5 10 15 Ser Phe Ser Asp Val Gly Met Pro Pro Pro Pro Ala Lys Trp Lys Gly 20 25 30 Phe Cys Glu Ser Asn Phe Thr Thr Lys Arg Asn Asn Lys Leu Ile Gly 35 40 45 Ala Arg Ser Phe Pro Leu Asp Asn Gly Pro Ile Asp Glu Asn Gly His 50 55 60 Gly Thr His Thr Ala Ser Thr Ala Ala Gly Ala Phe Val Lys Gly Ala 65 70 75 80 Asn Val Phe Gly Asn Ala Asn Gly Thr Ala Val Gly Val Ala Pro Leu 85 90 95 Ala His Ile Ala Ile Tyr Lys Val Cys Gly Ser Asp Gly Val Cys Ser 100 105 110 Asp Val Glu Ile Leu Pro Ala Met Asp Val Ala Ile Asp Asp Gly Val 115 120 125 Asp Ile Leu Ser Ile Ser Leu Gly Gly Thr Ser Asn Pro Phe His Asn 130 135 140 Asp Lys Ile Ala Leu Gly Ala Tyr Ser Ala Thr Glu Arg Gly Ile Leu 145 150 155 160 Val Ser Cys Ser Ala Gly Asn Ser Gly Pro Phe Gln Arg Thr Val Asn 165 170 175 Asn Asp Ala Pro Trp Ile Leu Thr Val Gly Ala Ser Thr His Asp Arg 180 185 190 Lys Leu Lys Ala Thr Val Lys Leu Gly Asn Lys Glu Glu Phe Glu Gly 195 200 205 Glu Ser Ala Tyr His Pro Lys Thr Ser Ser Ser Thr Phe Phe Thr Leu 210 215 220 Phe Asp Val Glu Lys Asp Gly Thr Arg Ala Thr Arg Ala Pro Phe Cys 225 230 235 240 Ile Pro Gly Ser Leu Thr Asp Pro Ser Ile Arg Gly Lys Ile Val Val 245 250 255 Cys Leu Val Gly Gly Gly Val Arg Thr Val Asp Lys Gly Gln Val Val 260 265 270 Lys Asp Ala Gly Gly Val Gly Met Ile Leu Ile Asn Asn Pro Glu Asp 275 280 285 Gly Val Thr Lys Ser Ala Glu Ala His Val Leu Pro Ala Leu Asp Val 290 295 300 Ser Asp Ala Asp Gly Lys Lys Ile Leu Ala Tyr Ile Asn Ser Thr Ser 305 310 315 320 Asn Pro Val Ala Ala Ile Thr Phe His Gly Thr Val Leu Gly Asp Lys 325 330 335 Asn Ala Pro Ile Val Ala Ser Phe Ser Ser Arg Gly Pro Ser Glu Ala 340 345 350 Ser Arg Gly Ile Leu Lys Pro Asp Ile Ile Gly Pro Gly Val Asn Val 355 360 365 Leu Ala Ala Trp Pro Thr Ser Val Asp Asn Asn Lys Asn Thr Lys Ser 370 375 380 Thr Phe Asn Ile Ile Ser Gly Thr Ser Met Ser Cys Pro His 385 390 395 26 166 PRT Nicotiana benthamiana 26 His Ala Ser Asp Gly Ala Gly His Ile Asn Pro Arg Lys Ala Val Asp 1 5 10 15 Pro Gly Leu Val Tyr Asp Ile Gly Ala Gln Asp Tyr Phe Glu Phe Leu 20 25 30 Cys Thr Gln Gln Leu Ser Pro Ser Gln Leu Thr Val Phe Gly Lys Phe 35 40 45 Ser Asn Arg Thr Cys His His Ser Leu Ala Asn Pro Gly Asp Leu Asn 50 55 60 Tyr Pro Ala Ile Ser Ala Val Phe Pro Glu Asp Ala Lys Val Ser Thr 65 70 75 80 Leu Thr Leu His Arg Thr Val Thr Asn Val Gly Ser Pro Ile Ser Asn 85 90 95 Tyr His Val Arg Val Ser Pro Phe Lys Gly Ala Val Val Lys Val Glu 100 105 110 Pro Ser Arg Leu Asn Phe Thr Ser Lys His Gln Lys Leu Ser Tyr Lys 115 120 125 Val Ile Phe Glu Thr Lys Tyr Arg Gln Lys Ala Arg Glu Phe Gly Ser 130 135 140 Leu Leu Trp Lys Asp Gly Thr His Lys Val Arg Ser Thr Ile Val Ile 145 150 155 160 Thr Trp Leu Ala Ser Ile 165 27 766 PRT Nicotiana benthamiana misc_feature (455)..(455) Xaa can be any naturally occurring amino acid 27 Met Ala Arg Pro Gly Gly Met Val Leu Ser Thr Leu Phe Leu Met Leu 1 5 10 15 Phe His Val Phe Val His Ala Gly Gln Asn Gln Lys Lys Thr Tyr Ile 20 25 30 Ile Tyr Met Asp Lys Ser Asn Ile Pro Ala Asp Phe Asp Asp His Thr 35 40 45 Leu Trp Tyr Asp Ser Ser Leu Lys Ser Val Ser Lys Gly Ala Asn Met 50 55 60 Leu Tyr Thr Tyr Asn Asn Val Ile His Gly Tyr Ser Thr Gln Leu Thr 65 70 75 80 Ala Asp Glu Ala Lys Ser Leu Glu Gln Gln Pro Gly Ile Leu Ser Val 85 90 95 His Glu Glu Val Arg Tyr Glu Leu His Thr Thr Arg Ser Pro Thr Phe 100 105 110 Leu Gly Leu Glu Gly Arg Glu Ser Lys Ser Phe Phe Leu Gln Ala Glu 115 120 125 Thr Arg Ser Glu Val Ile Ile Gly Val Leu Asp Thr Gly Val Trp Pro 130 135 140 Glu Ser Lys Ser Phe Asp Asp Thr Gly Leu Gly Pro Val Pro Met Ser 145 150 155 160 Trp Lys Gly Glu Cys Gln Ile Gly Lys Asn Phe Lys Ala Ser Ser Cys 165 170 175 Asn Arg Lys Leu Ile Gly Ala Arg Phe Phe Ser Gln Gly Tyr Glu Ala 180 185 190 Ala Phe Gly Ala Ile Asp Glu Thr Thr Glu Ser Lys Ser Pro Arg Asp 195 200 205 Asp Asp Gly His Gly Thr His Thr Ala Thr Thr Ala Ala Gly Ser Val 210 215 220 Val Thr Gly Ala Ser Leu Phe Gly Tyr Ala Ala Gly Thr Ala Arg Gly 225 230 235 240 Met Ala Ser His Ala Arg Val Ala Ala Tyr Lys Val Cys Trp Ala Gly 245 250 255 Gly Cys Phe Ser Ser Asp Ile Leu Ala Gly Met Asp Gln Ala Val Ile 260 265 270 Asp Gly Val Asn Val Leu Ser Leu Ser Leu Gly Gly Thr Ile Ser Asp 275 280 285 Tyr Tyr Arg Asp Ile Val Ala Ile Gly Gly Phe Ser Ala Ala Ser Gln 290 295 300 Gly Ile Phe Val Ser Cys Ser Ala Gly Asn Gly Gly Pro Gly Ser Gly 305 310 315 320 Ser Leu Ser Asn Ala Ala Pro Trp Ile Thr Thr Val Gly Ala Gly Thr 325 330 335 Met Asp Arg Glu Phe Pro Ala Tyr Ile Ser Leu Gly Asn Gly Lys Lys 340 345 350 Phe Ser Gly Val Ser Leu Tyr Ser Gly Lys Ala Leu Pro Ser Ser Val 355 360 365 Met Pro Leu Val Tyr Ala Gly Asn Ala Ser Gln Ala Ser Asn Gly Asn 370 375 380 Leu Cys Thr Ser Gly Ser Leu Ile Pro Glu Lys Val Asp Gly Lys Ile 385 390 395 400 Val Val Cys Asp Arg Gly Met Asn Ala Arg Ala Gln Lys Gly Leu Val 405 410 415 Val Lys Asp Ala Gly Gly Ile Gly Met Ile Leu Ala Asn Thr Asp Ser 420 425 430 Tyr Gly Asp Glu Leu Val Ala Asp Ala His Leu Ile Pro Thr Gly Ala 435 440 445 Val Gly Gln Thr Ala Gly Xaa Leu Ile Xaa Arg Tyr Ile Ala Ser Asp 450 455 460 Ser Asn Pro Ile Thr Thr Ile Ala Phe Gly Gly Thr Lys Leu Gly Val 465 470 475 480 Gln Pro Ser Pro Val Val Ala Ala Phe Ser Ser Arg Gly Pro Asn Pro 485 490 495 Ile Thr Pro Glu Ile Leu Lys Pro Asp Leu Ile Ala Pro Gly Val Asn 500 505 510 Ile Leu Ala Gly Trp Thr Gly Lys Val Gly Pro Thr Gly Leu Pro Glu 515 520 525 Asp Thr Arg Asn Val Gly Phe Asn Ile Ile Ser Gly Thr Ser Met Ser 530 535 540 Cys Xaa His Val Ser Gly Leu Ala Ala Xaa Leu Xaa Ala Ala His Pro 545 550 555 560 Glu Trp Ser Xaa Gly Val Ile Arg Ser Ala Leu Met Thr Thr Gly Tyr 565 570 575 Ser Thr His Lys Asn Gly Xaa Met Ile Glu Asp Val Ala Thr Gly Met 580 585 590 Ser Tyr Thr Pro Val Asp His Gly Ala Gly His Val Asn Pro Ala Ala 595 600 605 Ala Met Asn Pro Gly Leu Xaa Tyr Asp Leu Thr Val Asp Asp Tyr Ile 610 615 620 Asn Phe Leu Cys Ala Leu Asp Tyr Ser Pro Ser Met Ile Lys Val Ile 625 630 635 640 Ala Lys Arg Asp Ile Ser Cys Xaa Asn Asn Lys Asp Ile Glu Leu Leu 645 650 655 Thr Leu Ile Thr His Leu Leu Pro Phe Leu Trp Lys Arg Ala Trp Gly 660 665 670 Glu His Ala Asn Ser Ser Ala Pro Thr Val Thr Arg Tyr Thr Arg Thr 675 680 685 Leu Thr Asn Val Gly Asn Pro Ala Thr Tyr Lys Ala Ser Val Ser Ser 690 695 700 Glu Met Gln Glu Val Lys Ile Gln Val Glu Pro Gln Thr Leu Thr Phe 705 710 715 720 Ser Arg Lys Lys Glu Lys Lys Thr Tyr Thr Val Thr Phe Thr Ala Ser 725 730 735 Ser Lys Pro Ser Gly Thr Thr Ser Phe Ala Arg Leu Glu Trp Ser Asp 740 745 750 Gly Gln His Val Val Ala Ser Pro Ile Ala Phe Ser Trp Thr 755 760 765 28 350 PRT Nicotiana benthamiana 28 Asp Arg Ile Glu Lys Gly Gln Ala Val Lys Asn Ala Gly Gly Val Gly 1 5 10 15 Met Ile Leu Ile Asn Arg Leu Gln Asp Gly Ser Thr Lys Ser Ala Asp 20 25 30 Ala His Val Leu Pro Ala Leu Asp Val Ser Phe Phe Asp Gly Phe Gln 35 40 45 Ile Thr Glu Tyr Met Lys Ser Thr Lys Asn Pro Val Ala Arg Ile Thr 50 55 60 Phe Gln Gly Thr Ile Ile Gly Asp Lys Asn Ala Pro Val Leu Ala Gly 65 70 75 80 Phe Ser Ser Arg Gly Pro Ser Thr Ala Ser Pro Gly Ile Leu Lys Pro 85 90 95 Asp Ile Ile Gly Pro Gly Val Asn Val Leu Ala Ala Trp Pro Thr Ser 100 105 110 Val Glu Asn Lys Thr Asn Thr Lys Ser Thr Phe Asn Ile Ile Ser Gly 115 120 125 Thr Ser Met Ser Cys Pro His Leu Ser Gly Val Ala Ala Leu Leu Lys 130 135 140 Ser Ala His Pro Thr Trp Ser Pro Ala Ala Ile Lys Ser Ala Ile Met 145 150 155 160 Thr Thr Ala Asp Thr Val Asn Leu Ala Asn Asn Pro Ile Leu Asp Glu 165 170 175 Met Leu Arg Pro Ala Asn Ile Phe Ala Ile Gly Ala Gly His Val Asn 180 185 190 Pro Ser Arg Ala Asn Asp Pro Gly Leu Val Tyr Asp Thr Gln Phe Lys 195 200 205 Asp Tyr Ile Ser Tyr Leu Cys Gly Leu Lys Tyr Thr Asp Arg Gln Met 210 215 220 Gly Ser Leu Leu Gln Arg Arg Thr Ser Cys Ser Lys Val Lys Ser Ile 225 230 235 240 Pro Glu Ala Gln Leu Asn Tyr Pro Ser Phe Ser Ile Ser Leu Gly Ala 245 250 255 Asn Gln Gln Thr Tyr Thr Arg Thr Val Thr Asn Val Gly Glu Ala Met 260 265 270 Ser Ser Tyr Arg Val Lys Ile Val Ser Pro Gln Asn Val Ser Val Val 275 280 285 Val Lys Pro Ser Thr Leu Lys Phe Thr Lys Leu Asn Gln Lys Leu Thr 290 295 300 Tyr Arg Val Thr Phe Ser Thr Thr Thr Asn Ile Thr Asn Met Glu Val 305 310 315 320 Val His Gly Tyr Leu Lys Trp Thr Ser Asp Lys His Phe Val Arg Ser 325 330 335 Pro Ile Ala Val Ile Leu Gln Glu His Glu Thr Pro Glu Asp 340 345 350 29 181 PRT Nicotiana benthamiana 29 Ala Ile Thr Ala Gly His Val Asn Pro Glu Ser Ala Ile Asp Pro Gly 1 5 10 15 Leu Ile Tyr Asp Thr Asp Thr Ser Asp Tyr Ile Asn Leu Leu Cys Ser 20 25 30 Leu Asn Tyr Thr Glu Lys Glu Met Lys Leu Phe Thr Asn Glu Ser Asn 35 40 45 Pro Cys Ser Gly Phe Thr Gly Ser Pro Leu Asp Leu Asn Tyr Pro Ser 50 55 60 Leu Ser Val Met Phe Arg Pro Asp Ser Ser Val His Val Val Lys Arg 65 70 75 80 Thr Leu Thr His Val Ala Val Ser Lys Pro Glu Val Tyr Lys Val Lys 85 90 95 Ile Leu Asn Leu Asn Ser Glu Lys Val Ser Leu Ser Ile Ser Pro Met 100 105 110 Glu Leu Met Phe Asn Glu Ser Leu Arg Lys Gln Arg Tyr Met Val Lys 115 120 125 Phe Glu Ser His His Ile Phe Asn Ser Ser Arg Lys Ile Ala Glu Gln 130 135 140 Met Ala Phe Gly Ser Ile Ser Trp Glu Ser Glu Lys His Asn Val Arg 145 150 155 160 Ser Pro Phe Ala Val Met Trp Val Gln Gln Asn Phe Asn Asn Ser Arg 165 170 175 Leu Tyr Lys Ile Thr 180 30 10 PRT Nicotiana benthamiana 30 Thr Thr His Thr Ser Gln Phe Leu Gly Leu 1 5 10 31 14 PRT Nicotiana benthamiana 31 Phe Gly Tyr Ala Thr Gly Thr Ala Ile Gly Ile Ala Pro Lys 1 5 10 32 24 DNA Artificial Sequence Used in PCR 32 gtcctaatcc ctagggattt aagg 24 33 19 DNA Artificial Sequence Used in PCR 33 ctttggaaat tgcagaaac 19 34 19 DNA Artificial Sequence Used in PCR 34 gtttctgcaa tttccaaag 19 35 45 DNA Artificial Sequence Used in PCR 35 gaattcgggg taccgcggcc gcgatatcct gcagggcgtt aactc 45 36 45 DNA Artificial Sequence Used in PCR 36 gaattcggta ccctgcagga tatcgcggcc gcggcgttaa ctcgg 45 37 42 DNA Artificial Sequence Used in PCR 37 tggttctgca gttatgcata ggcgtgatta tcggagttat ag 42 38 37 DNA Artificial Sequence Used in PCR 38 tttccttttg cggccgcgtg agggcaagac attgatg 37 39 249 PRT Nicotiana benthamiana 39 Gly Val Ile Ile Gly Val Ile Asp Thr Gly Ile Val Pro Asp His Pro 1 5 10 15 Ser Phe Ser Asp Val Gly Met Pro Pro Pro Pro Ala Lys Trp Lys Gly 20 25 30 Phe Cys Glu Ser Asn Phe Thr Thr Lys Cys Asn Asn Lys Leu Ile Gly 35 40 45 Ala Arg Ser Phe Pro Leu Asp Asn Gly Pro Ile Asp Glu Asn Gly His 50 55 60 Gly Thr His Thr Ala Ser Thr Ala Ala Gly Ala Phe Val Lys Gly Ala 65 70 75 80 Asn Val Phe Gly Asn Ala Asn Gly Thr Ala Val Gly Val Ala Pro Leu 85 90 95 Ala Tyr Ile Ala Ile Tyr Lys Val Cys Gly Ser Asp Gly Val Cys Ser 100 105 110 Asp Val Glu Ile Leu Ala Ala Met Asp Val Ala Ile Asp Asp Gly Val 115 120 125 Asp Ile Leu Ser Ile Ser Leu Gly Gly Thr Ser Asn Pro Phe His Asn 130 135 140 Asp Lys Ile Ala Leu Gly Ala Tyr Ser Ala Thr Glu Arg Gly Ile Leu 145 150 155 160 Val Ser Cys Ser Ala Gly Asn Ser Gly Pro Phe Gln Arg Thr Val Asp 165 170 175 Asn Asp Ala Pro Trp Ile Leu Thr Val Gly Ala Ser Thr His Asp Arg 180 185 190 Lys Leu Lys Ala Thr Val Lys Leu Gly Asn Lys Glu Glu Phe Glu Gly 195 200 205 Glu Ser Ala Tyr His Pro Lys Thr Ser Asn Ser Thr Phe Phe Thr Leu 210 215 220 Phe Asp Val Glu Lys Ile Val His Glu Gln Pro Val Ala Pro Phe Cys 225 230 235 240 Ile Pro Gly Ser Leu Thr Asp Pro Ser 245 40 249 PRT Nicotiana benthamiana 40 Gly Val Ile Ile Gly Val Ile Asp Thr Gly Ile Val Pro Asp His Pro 1 5 10 15 Ser Phe Ser Asp Val Gly Met Pro Pro Pro Pro Ala Lys Trp Lys Gly 20 25 30 Phe Cys Glu Ser Asn Phe Thr Thr Lys Cys Asn Asn Lys Leu Ile Gly 35 40 45 Ala Arg Ser Phe Pro Leu Asp Asn Gly Pro Ile Asp Glu Asn Gly His 50 55 60 Gly Thr His Thr Ala Ser Thr Ala Ala Gly Ala Phe Val Lys Gly Ala 65 70 75 80 Asn Val Phe Gly Asn Ala Asn Gly Thr Ala Val Gly Val Ala Pro Leu 85 90 95 Ala Tyr Ile Ala Ile Tyr Lys Val Cys Gly Ser Asp Gly Val Cys Ser 100 105 110 Asp Val Glu Ile Leu Ala Ala Met Asp Val Ala Ile Asp Asp Gly Val 115 120 125 Asp Ile Leu Ser Ile Ser Leu Gly Gly Thr Ser Asn Pro Phe His Asn 130 135 140 Asp Lys Ile Ala Leu Gly Ala Tyr Ser Ala Thr Glu Arg Gly Ile Leu 145 150 155 160 Val Ser Cys Ser Ala Gly Asn Ser Gly Pro Phe Gln Arg Thr Val Asp 165 170 175 Asn Asp Ala Pro Trp Ile Leu Thr Val Gly Ala Ser Thr His Asp Arg 180 185 190 Lys Leu Lys Ala Thr Val Lys Leu Gly Asn Lys Glu Glu Phe Glu Gly 195 200 205 Glu Ser Ala Tyr His Pro Lys Thr Ser Asn Ser Thr Phe Phe Thr Leu 210 215 220 Phe Asp Val Glu Lys Ile Val His Glu Gln Pro Val Ala Pro Phe Cys 225 230 235 240 Ile Pro Gly Ser Leu Thr Asp Pro Ser 245 

What is claimed is:
 1. A host cell comprising one or more polynucleotides, wherein said one or more polynucleotides encode a protein of interest and a genetic element capable of reducing a protease activity in a host cell or fluids, wherein said one or more polynucleotides is capable of expressing said protein of interest in the host cell, wherein said protease activity is capable of cleaving said protein of interest, wherein said protein of interest is non-native to the host cell.
 2. The host cell according to claim 1, wherein said genetic element (1) expresses an antisense or sense element capable of reducing expression of a protein with said protease activity in said host cell, (2) expresses a ribozyme capable of reducing expression of a protein with said protease activity in said host cell, (3) induces expression of a protease inhibitor native to said host cell in said host cell, or (4) expresses a protease inhibitor in said host cell.
 3. The host cell according to claim 2, wherein said genetic element expresses an antisense or sense element capable of reducing expression of a protein with said protease activity in said host cell.
 4. The host cell according to claim 3, wherein said antisense or sense element comprises a nucleotide sequence that is substantially similar to the antisense or sense nucleotide sequence of a protease.
 5. The host cell according to claim 4, wherein said antisense or sense element comprises the antisense or sense nucleotide sequence of said protease.
 6. The host cell according to claim 5, wherein said host cell is a plant cell.
 7. The host cell according to claim 5, wherein said protease is native to said host cell.
 8. The host cell according to claim 5, wherein said protease is a serine protease.
 9. The host cell according to claim 8, wherein said serine protease is a chymotrypsin-like serine protease or a subtilisin-like serine protease.
 10. The host cell according to claim 9, wherein said subtilisin-like serine protease is a Nicotianalisin protein and the host is a plant cell.
 11. The host cell according to claim 1, wherein said protein of interest is a protein not native to the host cell.
 12. The host cell according to claim 11, wherein said protein is a human protein.
 13. The host cell according to claim 12, wherein said human protein is human growth hormone.
 14. The host cell according to claim 1, wherein said first polynucleotide is non-native to said host cell.
 15. The host cell according to claim 14, wherein said polynucleotide encoding the protein of interest inserted into a viral vector.
 16. The host cell according to claim 15, wherein said viral vector is obtained from a RNA virus.
 17. The host cell according to claim 11, wherein said host cell is a plant cell.
 18. The plant cell according to claim 17, wherein said one or more polynucleotides is in a vector.
 19. The plant cell according to claim 17, wherein the polynucleotide encoding a protein of interest and/or the polynucleotide encoding a genetic element capable of reducing a protease activity is integrated into the plant genome.
 20. The host cell according to claim 1, wherein said polynucleotide encoding the genetic element is inserted into a viral vector.
 21. The host cell according to claim 1, wherein said genetic element encodes a protease inhibitor.
 22. The host cell according to claim 21, wherein said protease inhibitor is aprotinin.
 23. The host cell according to claim 21, wherein said genetic element and said polynucleotide encoding a protein of interest are both inserted into a vector.
 24. The plant cell according to claim 23, wherein said polynucleotides encoding said genetic element and said protein of interest are fused together to produce a fused protein product. 25 The plant cell comprising the plant cell according to claim
 6. 26. A plant comprising the plant cell according to claim
 17. 27. A polynucleotide comprising a substantially similar or complementary sequence of at least a part of the coding sequence, or one or more fragments, of a Nicotianalisin protease which is not identical with another protease.
 28. A method of reducing the amount of a protein of interest cleaved by a hydrolase activity in a host cell, comprising the steps of: (a) introducing a polynucleotide into a host cell, wherein said polynucleotide comprises a genetic element capable of reducing a hydrolase activity in said host cell; and (b) expressing a protein of interest in said host cell, wherein said protein of interest is capable of expression in said host cell, wherein said protein of interest is capable of being cleaved by said hydrolase activity; whereby the amount of protein of interest cleaved by said hydrolase activity in said host cell is reduced compared to the amount of protein of interest cleaved by said hydrolase activity in another host cell in which said polynucleotide is not introduced.
 29. The method of claim 28 wherein said protein of interest is heterologous to said host.
 30. The method according to claim 28, further comprising the step of isolating the protein of interest from said host cell or fluid.
 31. The method according to claim 28 wherein said host cell is a plant cell.
 32. The method of claim 29 wherein said polynucleotide is in a vector.
 33. The method of claim 29 wherein said hydrolase is a protease.
 34. A vector containing a genetic element capable of reducing protease activity and a polynucleotide encoding a protein of interest.
 35. A composition of purified Nicotianalisin having a specific activity greater than 100 units/mg protein.
 36. The composition of claim 34 wherein Nicotianalisin is substantially isolated from other proteins and having an activity greater than 3000 units/mg protein.
 37. A method for cleaving a polypeptide comprising contacting a composition containing the Nicotianalisin of claim 35 with a polypeptide substrate for a time and under conditions sufficient to cleave the polypeptide. 